about windows xp

CPUS USED IN PERSONAL COMPUTERS

• Intel Processors

• AMD Processors

• Cyrix Procesors

• Motorola Processors

• RISC Processors

INTEL PROCESSORS

•Since 1978, Intel’s processors have evolved from the
8086 and the 8088 to the 80286, 80386, and 80486, to
the Pentium family of procesors. Al are part of the
80×86 line.

•Intel’s Pentium family of procesors includes the
Pentium, Pentium Pro, Pentium with MMX, Pentium
II, Pentium II, Pentium IV, Celeron, and Xeon
procesors.

•The earliest Intel procesors included only a few
thousand transistors. Today’s Pentium procesors
include 9.5 milion transistors or more.

•Intel knows that big numbers are impressive so they
have focused on developing faster procesors as
opposed to beter processors. Intel’s processors
perform wel in streaming multimedia type
applications, but they do not perform quite as wel in
ofice or productivity type applications.

•Under the Intel name there are 2 main consumer
lines: the Pentium, and the Celeron. The major
diference between these two is the fact that the
Celeron’s contain less internal cache. Internal cache is like temporarystorage within the procesor itself, it
gives the processor a shorter time between command
executions.

AMD PROCESSORS

• Advanced Micro Devices (AMD) was long known as a
provider of lower-performance procesors for use in
low-cost computers.

AMD performs beter for productivity or ofice based
applications like word procesing, web browsing, and
email. AMDs are also typicaly cheaper than Intels.

• With its K6 line of procesors, AMD chalenged Intel’s
procesors in terms of both price and performance.

• With the K6-III processor, AMD broke the 600 MHz
barrier, claiming the “fastest processor” title for the
first time in IBM-compatible computers.

CYRIX PROCESSORS

• Cyrix began as a specialtychip maker, but eventualy
began producing microprocessors.

• Cyrix processors are most commonly used in low-
price, low-end consumer PCs.

• Cyrix formerly produced the MediaGX processor, and
nowproduces the MII series of processors.

MOTOROLA PROCESSORS

• Motorola makes the CPUs used in Macintosh and
PowerPC computers.

• Macintosh procesors use a diferent basic structural
design (architecture) than IBM-compatible PC
procesors.

• With the release of the G3 and G4PowerPC processors,
Macintosh computers set new standards for price and
performance.

MOTOROLA PROCESSORS

• Motorola makes the CPUs used in Macintosh and
PowerPC computers.

• Macintosh procesors use a diferent basic structural
design (architecture) than IBM-compatible PC
procesors.

• With the release of the G3 and G4PowerPC processors,
Macintosh computers set new standards for price and
performance.

CISC AND RISC PROCESSORS

•Every CPU has the built-in ability to execute a
particular set of machine instructions, caled its
instruction set.

•Most CPU have 200 or more instructions (such as
add, subtract and compare) in their instruction set.

•CPU made by diferent manufacturer have diferent
instruction sets.

•When new CPU is developed it is ensured that its
instruction set includes al the instructions in the
instruction set of its predecessor CPU, plus some new
ones : upward compatibility

•MostPCsare based on complexinstructionset computing
(CISC)chips which containlargeinstructionsets.

•CSIC procesorsareCPUwith largeinstructionsets, variable-
lengthinstructionsand varietyofaddresing modes.

•Reducedinstructionsetcomputing(RISC)procesors use
smalerinstructionsets. Thisenables them to proces more
instructionspersecond than(CISC) chips.

•RISC procesorare CPUs with asmal instruction sets,fixed
lengthinstructions.

•RISC procesorsarefound in Apple’sPowerPC systems,as wel
as many H/PCs, workstations, minicomputers,and mainframes.

•EPIC Procesors (Explicitly ParalelInstruction Computing)
technology is fast emerging as the technologyforthenext
generationprocesors.HP andIntel havealready adopted itin
defining their 64-bit ISA knownas IA-64

PARALEL PROCESSING

•In paralel processing, multiple procesors are used in a
single system, enabling them to share procesing tasks.

•In a massively paralel processor (MPP) system, many
procesors are used.

•Some MPP systems utilize thousands of processors
simultaneously.

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Database Management Systems and Enterprise Software

Databases and Database Management Systems – The Diference between Databases and DBMSes

•A database is a repository for colections of related data or facts.

•A database management system (DBMS) is a software tool that lets users add, view, and work with the data in a database.

•Large databases and DBMS’ are commonly used by companies, but many productivity applications are built around database concepts.

Databases and DBMSes – Database Basics

Databases use three main structures for organizing
data:

•Fields, which store various pieces of data related to a single entity.

•Records, or colections of fields relating to an entity.

•Tables, which are colections of related records.

The two primary types of databases are flat-file databases (with only one table) and relational databases (with multiple, related tables).

Databases and DBMSes – DBMS Basics

A DBMS alows users to access and manage the data colected in a database.

Data management tasks (al done through the DBMS) can be divided into three categories:

•Entering data into the database.

•Sorting (rearranging) thedata in the database.

•Obtaining subsets of the data for use.

• Colection of interrelated data : DATABASE
• Set of programs to access the data : DBMS
• DBMS contains information about a particular enterprise
• DBMS provides an environment that is both convenient and eficient to use.

• Database Applications:

– Banking: al transactions

– Airlines: reservations, schedules

– Universities: registration, grades

– Sales: customers, products, purchases

– Manufacturing: production, inventory, orders, supply chain

– Human resources: employee records, salaries, tax deductions

• Databases touch al aspects of our lives

• In the early days, database applications were
built on top of file systems
• Drawbacks of using file systems to store data:
– Data redundancy and inconsistency
• Multiple file formats, duplication of information in
diferent files
– Difficulty in accessing data
• Need to write a new program to cary out each new task
– Data isolation — multiple files and formats
– Integrity problems
• Integrity constraints (e.g. account balance> 0) become
part of program code
• Hard to add new constraints or change existing ones

Purpose of Database Systems (Cont.)

• Drawbacks of using file systems (cont.)

– Atomicity of updates

• Failuresmay leave databasein an inconsistent state with partial updates caried out

• E.g.transferof funds from oneaccounttoanother should either complete or not happenat all

– Concurent acces by multiple users

• Concurentacesednededforperformance

• Uncontroled concurentacesescan lead toinconsistencies

– E.g.twopeoplereading abalanceand updating it at thesame time

– Security problems

• Database systems offer solutions to al the above problems

Data Definition Language (DDL)

• Specification notation for defining the database schema

• DDL compiler generates a set of tables stored in a data dictionary

• Data dictionary contains metadata (i.e., data about data)

– database schema

– Data storage and definition language

• languagein whichthestoragestructure and aces methodsused by the database system are specified

• Usualy an extensionofthe datadefinitionlanguage

Data Manipulation Language (DML)

• Language for accessing and manipulating the data organized by the appropriate data model

– DML also known as query language

• Two classes of languages

– Procedural – user specifies what data is required and how to get those data

– Nonprocedural – user specifies what data is required without specifying how to get those data

• SQL is the most widely used query language

Database Users

• Users are differentiated by the way they expect to interact with the system

• Application programmers – interact with system through DML cals

• Sophisticated users – form requests in a database query language

• Specialized users – write specialized database applications that do not fit into the traditional data processing framework

• Naïve users – invoke one of the permanent application programs

– E.g. people accesing database over the web, bank telers, clerical staf

Database Administrator

• Coordinates al the activities of the database system; the database administrator has a good understanding of the enterprise’s information resources and needs.

• Database administrator’s duties include:

– Schema definition

– Storage structure and access method definition

– Schema and physical organization modification

– Granting user authority to acces the database

– Specifying integrity constraints

– Acting as liaison with users

– Monitoring performance and responding tochanges in requirements

Working With a Database

• Creating Database Tables

• Viewing Records

• Sorting Records

• Querying a Database

• Generating Reports

Creating Database Tables

• The first step in building a database is to create its tables. This means identifying, naming, and organizing its fields to receive data.

• Databases can store the folowing types of fields:

• You can create forms that let you view and enter data for one record at a time.

• Database tools such as masks can validate data as it is entered and thus ensure the data is in the correct format.

Viewing Records

• A filter is a tool that lets you view records that match a given criteria.

• Filters are helpful when searching for certain types of information in a large database with many records.

• A form can work with a filter, but enables you to view information about a single record.

Sorting Records

• Sorting means arranging the records in a database.

• A DBMS enables you to sort records alphabeticaly, numericaly, and chronologicaly.

• You can sort records in ascending (A-Z) order or descending (Z-A) order.

Querying a Database

A query is a statement you define, which tels the DBMS to find records that match criteriayou specify.

Modern DMBS software provides built-in querying tools, based on one or more of the folowing languages:

• SQL

• Query by Example (QBE)

• Xbase

Generating Reports

• A report is a subset of information from a database, produced in printed form.

• You can generate the data for a report by using a query, filter, or other tools.

• Reports can be formated in a wide variety of ways.

Enterprise Software

•Enterprise software is a large-scale application based
on a DBMS, used by a large organization.

•Enterprise software can meet the needs of many
diferent users in diferent locations.

•In an enterprise, diferent users by have diferent
interfaces to the database, so they can work only with
the data they need.

How Networks are Structured

OSI Model

• Application layer : File Transfer, access

• Presentation layer : Data encryption, Compression

• Session : Resynchronization

• Transport: Error detection and recovery

• Network: Logical addressing, Routing

• Data Link: Framing, Physical Addressing

• Physical Layer : Network card, Cabling

Local Area Networks (LANs)

• A LAN is a network whose computers are located relatively near one another. The nodes may be connected by a cable, infrared link, or smal transmiters.

• A network transmits data among computers by breaking it into smal pieces, caled packets.

• Every LAN uses a protocol – a set of rules that governs how packets are configured and transmited.

Wide Area Networks (WANs)

• Multiple LANs can be connected together using devices such as bridges, routers, or gateways, which enable them to share data.

• A WAN is two or more LANs connected together. The LANs can be many miles apart.

• To cover great distances, WANs may transmit data over leased high-speed phone lines or wireless links such as satelites.

Server-Based Networks

• In addition to the individual users’ PCs (nodes), many networks use a central computer, caled a server.

• A server has a large hard disk for shared storage. It may provide other services to the nodes, as wel.

• In a file server network, nodes can acces files on the server, but not necessarily on other nodes.

Client/Server Networks

•In client/server computing, individual nodes share the processing and storage workload with the server.

•Client/server networks require specialized software that enables nodes and the server to colaborate on processing and storage, but no special type of network hardware.

Peer-to-Peer Networks

•In a peer-to-peer network, al nodes have an equal relation to one another.

•Each node usualy has access to some resources on other nodes, so users can share files, programs, or deviceson other users’ systems.

•Some peer-to-peer networks use a server, but some do not.

Network Topologies for LANs

A network’s topology is the layout of the cables and devices that connect the nodes. The four most common network topologies are:

•Bus. Each node is connected in series along a single conduit.

•Star. Al nodes are connected to a central hub.

•Ring. Nodes are connected in a circular chain, with the conduit beginning and ending at the same computer.

•Mesh. Each node has a separate connection to every other node.

________________________________________________________-MEASURING DRIVE PERFORMANCE

1. AVERAGE ACCESS TIME

•In storage devices, average acces time (or seek
time) is thetime required for a read/write head to
move to a spot on the storage medium.

•For storage devices, access time is measured in
miliseconds (ms), or thousandths of a second. In
memory, access time is measured in nanoseconds
(ns), or one-bilionths of a second.

•Diskete drives ofer an average access time of 100
ms. Hard drives are faster, usualy between 6 – 12
ms.

2. FILE COMPRESSION

•File compression technologyshrinks files so they take
up less disk space.

•Using a compression utility, you can shrink multiple
files into a single archive file.

•Utilities such as Windows’ DriveSpace enable you to
compress the entire contents of yourhard disk.

3. DATA-TRANSFER RATE

•Data-transfer rate (or throughput) measures the time
required for data to travel from one device to another.

•If a device transfers 45,000 bytes per second, its data-
transfer rate is 45 KBps.

•Hard disks ofer the fastest data-transfer rates of any
storage device.

4. DRIVE-INTERFACE STANDARDS

•Al PCs use a disk controler as an interface between
a disk drive and the CPU. The two most common
interface standards are EIDE and SCSI.

•EIDE has evolved over the years and has several
variants, al of which have diferent names.

•SCSI is a faster, more flexible drive-interface
standard found in high-performance computers.

_______________________________________________________

Network Media and Hardware

• In a network, the media are the wires, cables and other means by which data travels from its source to its destination.

• The most common network media are twisted-pair cable, coaxial cable, fiber-optic cable, and wireless links.

• Each node uses a special device, caled a network interface card (NIC). The card connects to the network media and controls the flow of data.

• NICs must use a common network technology to communicate. The most popular network technologies for LANs are Ethernet, Fast Ethernet, and Token Ring.

Data Transfer Mode

Refers to the direction of signal flow between two linked devices

• Simplex: Unidirectional flow. The information flows in one across the circuit, with no capability to support response in the other direction.

• Half –Duplex : Each communicating device can receive and transmit information but not at the same time.

• Ful-duplex : It alows the communicating devices to transmit and receive data simultaneously

Data Communication Measurement

The amount of datathat can be transmited over a network at any given time. Bandwidth may be measured in bits per second (bps) or in hertz (Hz) Fundamentaly bandwidth refers to the maximum volume of information that can be transfered over any communication medium.

The level of bandwidth fals into three categories :

Narrowband : Thereisa single transmission channel of 64 Kbps or less. There can be also be a number of 64 Kbps transmission (N x 64 kbps) but not more than 1.544 Mbps

Wideband : Bandwidth capacity lies between 1.5444 Mbps – 45 Mbps

Broadband : The bandwidth capacity is equal to 45 Mbps

Transmission media

• Guided :uses a cabling system thatguides thedata signal alongaspecific
path. Therearefourbasictypes of guidedmedia:Open wire, twisted pair,coaxial cableandoptical fiber

• Unguided :datasignalflowsthrough theairRadio frequency propagation –

Groundwave propagation( carierfrequencies upto 2MHz.)

Ionospherepropagation(frequency rangeof30 -85MHz)

Microwave -Microwavetransmisionisline ofsighttransmision. This setsalimit onthe distance betwen stations depending onthe local geography. Typicaly line of sight dueto earth’scurvature is only50 km to the horizon.

Satelite-It is also a kind of line of sight transmision. These are set ingeostationary orbitsdirectlyover theequator, which rotates in synchronization to earth and hence look stationary from any point on earth. These are placed 36,000 km above the earth’s surface. The communication is caried out through uplinks and downlinks.

Network Media and Hardware

• HUB : A smal box that connects individual devices on a network so tat they can communicate with one another. It operates by gathering the signal from
individual networkdevices, optionaly amplifying the signal, and then sending them onto al other connected device.

• Switch : Like a hub, Switch too connects individual devices on a network so that they can communicate with one another. They are capable ofinspecting thedata packets, and forwardingthat packet appropriately. Hub, in contrast broadcast al information to each connected computer, whether or not that computer is the intended receipt.

• Bridge : It inspects incoming trafic and decides whether to forward or discard it. The bridge regenerates the incoming frame signal and checks the
address of the destination and forwards the new copy only to the segments towhich the addres belongs.

• Router : Router is an essential network device for interconnecting two or more networks. Router’s sole aim is to trace the best route for information to travel. A router creates and or maintains a table, caled routing table that stores the best routes to certain network destination.

• Gateway : An internetworking device, which joins two diferent network protocols together. It is also caled protocol converter. It accepts the packet formated forone protocol and converts the formated packet into another protocol.

*******************************************************************88Network Software

A network operating system (NOS) is the group of programs that manages the resources on a network.Common network operating systems for PC-based networks include:

•Novel NetWare

•Microsoft Windows NTServer

•Microsoft Windows 2000

•Banyan VINES

•AppleShare

•Linux
Network Topologies for LANs

A network’s topology is the layout of the cables and
devices that connect the nodes. The four most common
network topologies are:

•Bus. Each node is connected in series along a
single conduit.

•Star. Al nodes are connected to a central hub.

•Ring. Nodes are connected in a circular chain,
with the conduit beginning and ending at the
same computer.

•Mesh. Each node has a separate connection to
every other node.

OPERATING SYSTEM BASICS

• The User Interface

• Running Programs

• Managing Files

• Managing Hardware

• Utility Software

The User Interface

– Graphical User Interfaces (GUIs)

•Most modern operating systems, like Windows and
the Macintosh OS, provide a graphical user interface
(GUI).

•A GUI lets youcontrol the system by using a mouse
to click graphical objects on screen.

•A GUI is based on the desktop metaphor. Graphical
objects appear on a background (the desktop),
representing resources you can use.

-GUI Tools

• Icons are pictures that represent computer
resources, such as printers, documents, and
programs.

• You double-click an icon to choose (activate) it, for
instance, to launch a program.

• The Windows operating system ofers two unique
tools, caled the taskbar and Start buton. These
help you run and manage programs.

-Applications and the Interface

• Applications designed to run under one operating
system usesimilarinterface elements.

• Under an OS such as Windows, you see a familiar
interface no mater what programs you use.

• In a GUI, each program opens and runs in a separate
window—a frame that presents the program and its
documents.

• In a GUI, you can run multiple programs at once,
each in a separate window. The application in use is
said to be the active window.

-Menus

•GUI-based programs let you isue commands by
choosing them from menus.

•A menu groups related commands. For example, the
File menu’s commands let you open, save, and print
document files.

•Menus let you avoid memorizing and typing
command names.

•In programs designed for the same GUI, menus and
commands are similar from one program to another.

-Dialog Boxes

•A dialog box is a special window that appears when
a programor the OS needs more information
before completing a task.

•Dialog boxes are so named because they conduct a
“dialog” with the user, asking the user to provide
more information ormake choices.

-Command-Line Interfaces

• Some older operating systems, such as DOS and
UNIX, use command-line interfaces.

• In a command-line interface,you type commands at a
prompt.

• Under command-line interfaces, individual
applications do not need to look or function the same
way, so diferent programs can look very diferent

Running Programs

-Basic Services

•The operating system manages al the other
programs that run on the PC.

•The operating system provides services to programs
and the user, including file management, memory
management, and printing

•To provide services to programs, theOSmakes
system cals—requesting other hardware and
software resources to perform tasks.

– Sharing Information

• Some operating systems, such as Windows, enable
programs to share information.

• You can create data in one program and use it again
in other programs without re-creating it.

• Windows provides the Clipboard, a special area that
stores data cut or copied from one document, so you
can re-use it elsewhere.

-Multitasking

•Multitasking is the capability of running multiple
proceses simultaneously.

•A multitasking OSlets you run multiple programs at
the same time.

•Through multitasking, you can do several chores at
one time, such as printing a document while
downloading a file from the Internet.

•There are two types of multitasking: cooperative and
preemptive.

Managing Files

• The operating system keeps track of al the files on
each disk.

• Users can make file management easier by creating
a hierarchical file system that includes folders and
subfolders arranged in a logical order.

Managing Hardware

•The OS uses interrupt requests (IRQs) to maintain
organized communication with the CPU and other
pieces of hardware.

•Each hardware device is controled by a piece of
software, called a driver, which allows the OS to
activate and use the device.

•The operating system provides the software necessary
to link computers and form a network.

Utility Software

A utility is a program that performs a task that is not
typically handled by the operating system.

Some utilities enhance the operating system’s
functionality.

Some of the major categories of utilities include:
• File defragmentation
• Data compression
• Backup
• Antivirus
• Screen savers

_____________________________________________________

Presentation Programs

Presentation Program Basics

•Presentation Programs and Their Uses

•The Presentation Program’s Interface

•Creating a Presentation

•Formating Slides

•Special Features of Presentation Programs

Presentation Programs and Their Uses

•Presentation programs are used tocreate slides–single-screen images that contain text, graphics, charts, and more.

•A colection of slides is caled a presentation.

•A presentation program lets you create a set of slides and show (present) them to an audience.

The Presentation Program’s Interface

Presentation programs provide many of the same editing and formating tools found in word processors and other common applications.

Presentation Program Basics –
Creating a Presentation

• To create a presentation, you can select a predesigned
template to create a common look for the slides.

• Individual slide elements appear inside text boxes and
.frames.

• You can easily add text or graphics to a box or frame,
and move or resize it as needed.

Formating Slides

You can format a slide by choosing diferent:

•Fonts and font sizes

•Colors

•Backgrounds

•Borders

To resize a frame or text box, click it, then drag one of its handles.

Special Features

Presentation programs provide several special features:

•Outlining—for contents, arrangement and order.

•Annotations—notes to individual slides.

•Animation—moving transitions to parts of a slide.

•Sound and video—audio or multimedia enhancement.

•Embedded objects—WWW links.

•HTML conversion—presentations on the Web.

Integrating Multiple Data Sources in a Presentation

•One can add diferent media types, such as audio or video files, to a slide.

•If you present your slides from the PC’s disk and have the appropriate output devices, you can present multimedia elements in a slide show.

Presenting Slide Shows

You can print slides and present them on a slide or overhead projector.

You also can display slides directly from the PC’s disk, with the folowing advantages:

•You can present them in any order you like.

•You can display slides on the PC’s monitor, project them on a screen, or connect the PC to a TV or large monitor.

•You can move from slide to slide manualy, or automate the presentation.

_____________________________________________________________________________
RUNNING PROGRAMS

1. BASIC SERVICES

2. SHARING INFORMATION

3. MULTITASKING

1. Basic Services

• The operating system manages al the other programs that run on the PC.
• The operating system provides services to programs and the user, including file management, memory management, and printing
• To provide services to programs, theOSmakes system cals—requesting other hardware and software resources to perform tasks.

2. Sharing Information

• Some operating systems, such as Windows, enable programs to share information.
• You can create data in one program and use it again in other programs without re-creating it.
• Windows provides the Clipboard, a special area that stores data cut or copied from one document, so you can re-use it elsewhere.

3. Multitasking

• Multitasking is the capability of running multiple proceses simultaneously.
• A multitasking OSlets you run multiple programs at the same time.
• Through multitasking, you can do several chores at one time, such as printing a document while downloading a file from the Internet.
• There are two types of multitasking: cooperative and preemptive.

__________________________________________________________–

Spreadsheet Software

Spreadsheet Programs and Their Uses

• Spreadsheets provide tools for working with numerical data.

• You can use a spreadsheet program to create budgets, balance sheets, and other types of number-based documents.

• You can display your information in a traditional row-and-column format, or in a chart.

The Spreadsheet’s Interface

•In a spreadsheet program, you work in a document caled a worksheet. You can colect multiple worksheets into a file caled a workbook.

•Most Windows-based word spreadsheets ofer a similar set of tools, including a formula bar, where you can enter and edit data.

•Data is displayed in cels. A cel is the intersection of a row and column.

•Each cel has a cel address – the combination of the cel’s column leter and row number.

Entering Data in a Worksheet- Types of Data

You enter four types of data in a worksheet’s cels:

•Labels-text or numbers not used in calculations.

•Values-numbers that can be used in calculations.

•Dates-a necesary part of most worksheets.

•Formulas-commands to perform calculations based on numbers or formulas.

Entering Data in a Worksheet- Formulas and Functions

•If a formula uses a value in another cel, the formula contains a cel reference, or the addres of the referred cel.

•Formulas can refer to entire ranges (or blocks) of contiguous cels as wel as individual cels.

•A function is a predefined formula, which the spreadsheet provides to perform a specific type of calculation. You provide arguments that tel the function what data to use.

Editing and Formatting a Worksheet

•Spreadsheets provide many of the same editing and
formating tools found in word processors.

•You can change, copy, move, and delete the data in
any cel.

Relative and Absolute Cel References

•If a formula uses a relative cel reference, it automaticaly dates if (copied or moved), to a diferent place.

•An absolute cel reference always refers to thesame cel even if the formula is moved to a diferent place.

Adding Charts

• A chart is a graphical representation of the data in a worksheet.

• Spreadsheets provide tools that make it easy to create a chart from worksheet data.

• You can use many diferent types of charts, and apply many efects to a chart, to present your data in the most appropriate way.

Analyzing Data in a Spreadsheet

Three commonly used data-analysis tools are:

•What-if analysis, which lets you test scenarios to see
how each afects the result.

•Goal seeking, which finds values that make the
result meet your specifications.

•Sorting, which lets you arrange the worksheet’s
data in various ways.

______________________________________________________________________________

THE USER INTERFACE

1. Graphical User Interfaces (GUIs)

•Most modern operating systems, like Windows and
the Macintosh OS, provide a graphical user interface
(GUI).

•A GUI lets youcontrol the system by using a mouse
to click graphical objects on screen.

•A GUI is based on the desktop metaphor. Graphical
objects appear on a background (the desktop),
representing resources you can use.

2. GUI Tools

• Icons are pictures that represent computer
resources, such as printers, documents, and
programs.

• You double-click an icon to choose (activate) it, for
instance, to launch a program.

• The Windows operating system ofers two unique
tools, caled the taskbar and Start buton. These
help you run and manage programs.

3. -Applications and the Interface

• Applications designed to run under one operating
system usesimilarinterface elements.

• Under an OS such as Windows, you see a familiar
interface no mater what programs you use.

• In a GUI, each program opens and runs in a separate
window—a frame that presents the program and its
documents.

• In a GUI, you can run multiple programs at once,
each in a separate window. The application in use is
said to be the active window.

4. -Menus

•GUI-based programs let you isue commands by
choosing them from menus.

•A menu groups related commands. For example, the
File menu’s commands let you open, save, and print
document files.

•Menus let you avoid memorizing and typing
command names.

•In programs designed for the same GUI, menus and
commands are similar from one program to another.

5. -Dialog Boxes

•A dialog box is a special window that appears when
a programor the OS needs more information
before completing a task.

•Dialog boxes are so named because they conduct a
“dialog” with the user, asking the user to provide
more information ormake choices.

6. -Command-Line Interfaces

• Some older operating systems, such as DOS and
UNIX, use command-line interfaces.

• In a command-line interface,you type commands at a
prompt.

• Under command-line interfaces, individual
applications do not need to look or function the same
way, so diferent programs can look very diferent
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The Uses of a Network

A network connects computers so they can communicate, exchange information, andshareresources.The main benefits of using a network are:

•Simultaneous Access

•Shared Peripheral Devices

•Personal Communication

•Easier Backup

Simultaneous Access

• In organizations, many people may need to use the same data or programs. A network solves this problem.

• Shared data and programs can be stored on a central network server. A server that stores data files may be caled a file server.

• Managers may asign access rights to users. Some users may only be able to read data, others may be able to make changes to existing files.

Shared Peripheral Devices

•Because peripheral (external) devices like printers can be expensive, it is cost-efective to connect a device to a network so users can share it.

•Through a process caled spooling, users can send multiple documents (caled print jobs) to a networked printer at the same time. The documents are temporarily stored on the server and printed in turn.

Personal Communication

• One of the most common uses of networks is for electronic mail (e-mail).

• An e-mail system enables users to exchange writen mesages (often with data files atached) acros the local network or over the Internet.

• Two other popular network-based communications systems are teleconferencing and videoconferencing.

Easier Backup

• Networks enable managers to easily back up (make backup copies of) important data.

• Administrators commonly back up shared data files stored onthe server, but may also use the network to back up files on users’ PCs.

TYPES OF STORAGE DEVICES

1. CATEGORIZING STORAGE DEVICES

2. MAGNETIC STORAGE DEVICES

3. OPTICAL STORAGE DEVICES

1. CATEGORIZING STORAGE DEVICES

• Storage devices hold data, even when the computer is turned of.

• The physical material that actualy holds data is caled a storage medium. The surface of a floppy disk is a storage medium.

• The hardware that writes data to or reads data from a storage medium is caled a storage device. A floppy disk drive is a storage device.

• The two primary storage technologies are magnetic and optical.

The primary types of magnetic storage are:

• Disketes (floppy disks)

• Hard disks

• High-capacity floppy disks

• Disk cartridges

• Magnetic tape

The primary types of optical storage are:

• Compact Disk Read-Only Memory (CD-ROM)

• Digital Video Disk Read-Only Memory (DVD-ROM)

o CD-Recordable (CD-R)

• CD-Rewritable (CD-RW)

• PhotoCD

2. MAGNETIC STORAGE DEVICES

– How Magnetic Storage Works

• A magnetic disk’s medium contains iron particles, which can be polarized—given a magnetic charge—in one of two directions.

• Each particle’s direction represents a 1 (on) or 0 (of), representing each bit of data that the CPU can recognize.

• A disk drive uses read/write heads containing electromagnets to create magnetic charges on the medium.

-Formatting

• Before a magnetic disk can be used, it must be formated—a process that maps the disk’s surface and determines how data wil be stored.

• During formating, the drive creates circular tracks around the disk’s surface, then divides each track into sectors.

• The OS organizes sectors into groups, caled clusters, then tracks each file’s location according to the clusters it occupies.

-Disk Areas

When a disk is formated, the OS creates four areas on its surface:

• Boot sector – stores the master boot record, a smalL program that runs when you first start (boot) the computer.

• File alocation table (FAT) – a log that records each file’s location and each sector’s status

• Root folder – enables the user to store data on the disk in a logical way

• Data area – the portion of the disk that actualy holds data

-Diskettes

• Diskete drives,alsoknown as floppy disk drives, read and write to disketes (caled floppy disks or floppies).

• Disketes are used to transfer files between computers, as a means for distributing software,and as a backup medium.
• •Disketes come in two sizes: 5.25-inch and 3.5-inch.

-Hard Disks

• Hard disks use multiple platers, stacked on a spindle. Each plater has two read/write heads, one for each side.

• Hard disks use higher-quality media and a faster rotational speed than disketes.

• Removable hard disks combine high capacity with the convenience of disketes.

-Disk Capacities

• Disketes are available in diferent capacities, but the most common store 1.44 MB.

• Hard disks storelarge amounts of data. New PCs feature hard disks with capacities of 10 GB and higher.

-Other Magnetic Storage Devices

• High-capacity floppy disks ofer capacities up to 250 MB and the portability of standard floppy disks.

• Disk cartridges are like smal removable hard disks, and can store up to 2 GB.

• Magnetic tape systems ofer very slow data access, but provide large capacities and low cost.

3. OPTICAL STORAGE DEVICES

-How Optical Storage Works

• An optical disk is a high-capacity storage medium.
• An optical drive uses reflected light to read data.
• To store data, the disk’s metal surface is covered with tiny dents (pits) and flat spots (lands), which cause light to be reflected diferently.
• When an optical drive shines light into a pit, the light cannot be reflected back. This represents a bit value of 0 (of). A land reflects light back to its source, representing a bit value of 1 (on).

-CD-ROM

• In PCs, the most commonly usedoptical storage technology is called Compact Disk Read-Only Memory (CD-ROM).

• A standard CD-ROM disk can store up to 650 MB of data, or about 70 minutes of audio.

• Once data is writen toa standard CD-ROM disk, the data cannot be altered or overwriten.

-CD-ROM Speeds and Uses

• Early CD-ROM drives were caled single speed, and read data at a rate of 150 KBps. (Hard disks transfer data at rates of 5 – 15 MBps).

• CD-ROM drives now can transfer data at speeds of up to 7800 KBps. Data transfer speeds are geting faster.
• CD-ROM is typicaly used to store software programs. CDs can store audio and video data, as wel as text and program instructions.

-DVD-ROM

• A variation of CD-ROM is caled Digital Video Disk Read-Only Memory (DVD-ROM), and is being used in place of CD-ROM in many newer PCs.

• Standard DVD disks store up to 9.4 GB of data—enough to store an entire movie. Dual-layer DVD disks can store up to 17 GB.

• DVD disks can store so much data because both sides of the disk are used, along with sophisticated data compression technologies.

-Other Optical Storage Devices

• A CD-Recordable (CD-R) drive lets you record your own CDs, but data cannot be overwriten once it is recorded to the disk.

• A CD-Rewritable (CD-RW) drive lets you record a CD, then write new data over the already recorded data.

• PhotoCD technology is used to store digital photographs.

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Upgrading Your PC

Introduction

EARLIER IT IS THE PEROGATIVE OF COMPUTER ENGINEERS AND WITH DUE COURSE OF TIME AND WITH THE VAAILABILITY OF MUCH INFORMATIONS FROM VARIOUS SOURCES AND AWARENESS AMONG PUBLIC , THE FEAR PSYCHOSIS IS REDUCING AMONG THE LAYMAN. AS THE NATURE OF MAN ALWAYS TO EXPLORE THE IN EVITABLE AND THIS VERY REASON COMPELLS THE MAN TO STEP IN THIS DIRECTION OF COURSE AFTER GARNERING ENOUGH KNOWLEDGE AND AWARENESSES.

• THE IMPORTANT THINGS YOU MUST BE RMEMEBERING AND TAKING CARE OF BEFORE UPGRADING YOUR PC.

CHECKPC shutdown INTERVALS AND ALSO SEE IF IT IS HANGING ON FOR WHATSO EVER NO REASON TO BE PUT ON THE TABLE . KEEP THE POWER SUPPLY LIKE CAPACITOR OR SOME OTHER COMPONENT CHECKED.
OVER HEATING MAY BE ONE OF THE PROBLEM AND IN THIS CASE OYU MAY ADD ONE MORE FAN OR ALSO KEEP THE WIRED CABLES IN THE PROPER ORDER SO THAT WIND MAY NOT BE BLOCKED IN BETWEEN.

AND GET A HARD DISK FAN. THIS CAN BE MOUNTED EITHER DIRECTLY ABOVE THE HARD DISK OR RIGHT IN FRONT OF IT. IF IT IS MOUNTED ABOVE THE HARD DISK, IT WILL TAKE UP THE SPACE OF ONE IDE DRIVE, BUT IT WILL BE WORTH IT. CAN DO ANOTHER SIMPLE THING TO INCREASE THE LIFE OF YOUR HARD DISK: GO TO THE POWER SAVER SETTINGS IN WINDOWS AND SET THE HARD DISKS TO TURN OF AFTER 3, 5, OR 10 MINUTES OF IDLING.

IF YOUR WINDOWS RUNNING SLOWLY THAT YOU HAVE ANTICIAPTED THEN TRY TO BUY MORE RAM , AS JUST REMEMEBR THAT WINDOWS XP TAKES LOTS OF RAM TO RUN MORE SMOOTHLY , HP WILL BE HAPPIER TO RECEIVE MORE AND MORE RAM , SO MAKE IT 512 MB OR 1 GB AND FOR THIS TEEL YOUR VENDOUR ALL THE REQUIREMENTS AND HE WILL BE TELLING YOU THE CAPAPCITY OF RAM WHICH YOUR REQUIRES.

IF YOU HAVE THE OLD COMPUTER WITH COMAPRATIVE GOOD SPEAKERS AND SOUND QUALITY NOT HIGH THEN CHECK OFR THE NEW SOUND CARD THAT MAY WORK WELL FOR THIS CASE .

IF YOU PC IS TAD SLOW THEN MAKE A THROUGH SCAN WITH THE FULLY UPDATED PROFESSIONAL VURIS SCANNER AND ALSO ANTI SPYWARE SCANNER AND ALSO RUN CCLEANER TO CLEAN THE UNNECESSRY FILES , AS SIMPLY UPGRADING THE PROCESSOR WILL NOT WORK YOU HAVE TO SEE THE ALL THE REQUIREMENTS SO THST SYSTEM WILL FUNCTION NORMAL AND SMOOTH.

CHOOSE THE RIGHT COMBINATIONS OF ANTI VIRUS, ANTI SPYWARE , FIREWALL AND HIPS AND FOR THIS SEE MY EARLIER ARTICLES AND IN THE MARKET LOTS OF FREEWARE AVAILABLE WHICH YOU DONONT HAVE TO SPEND A PIE FOR FULL PROOF SEUCURITY. AS WRONG COMBINATIONS OF THESE SECURITY PRODUCTS MAY CAUSE THE PC TO RUN SLOW SOME TIMES.

IF YOU SYSTEM IS REBOOTING CONSTANT LY THEN UPGRADE TO WINDOWS XP AS IT IS MORE STABLE IN FACT ABOVE 90 PC MORE STABLE THAN THE WINDOWS 98.

Working With a Database

• Creating Database Tables

• Viewing Records

• Sorting Records

• Querying a Database

• Generating Reports

Creating Database Tables

• The first step in building a database is to create its tables. This means identifying, naming, and organizing its fields to receive data.

• Databases can store the folowing types of fields:

• You can create forms that let you view and enter data for one record at a time.

• Database tools such as masks can validate data as it is entered and thus ensure the data is in the correct format.

Viewing Records

• A filter is a tool that lets you view records that match a given criteria.

• Filters are helpful when searching for certain types of information in a large database with many records.

• A form can work with a filter, but enables you to view information about a single record.

Sorting Records

• Sorting means arranging the records in a database.

• A DBMS enables you to sort records alphabeticaly, numericaly, and chronologicaly.

• You can sort records in ascending (A-Z) order or descending (Z-A) order.

Querying a Database

A query is a statement you define, which tels the DBMS to find records that match criteriayou specify.

Modern DMBS software provides built-in querying tools, based on one or more of the folowing languages:

• SQL

• Query by Example (QBE)

• Xbase

Generating Reports

• A report is a subset of information from a database, produced in printed form.

• You can generate the data for a report by using a query, filter, or other tools.

• Reports can be formated in a wide variety of ways.

Enterprise Software

•Enterprise software is a large-scale application based
on a DBMS, used by a large organization.

•Enterprise software can meet the needs of many
diferent users in diferent locations.

•In an enterprise, diferent users by have diferent
interfaces to the database, so they can work only with
the data they need.

Working With a Database

• Creating Database Tables

• Viewing Records

• Sorting Records

• Querying a Database

• Generating Reports

Creating Database Tables

• The first step in building a database is to create its tables. This means identifying, naming, and organizing its fields to receive data.

• Databases can store the folowing types of fields:

• You can create forms that let you view and enter data for one record at a time.

• Database tools such as masks can validate data as it is entered and thus ensure the data is in the correct format.

Viewing Records

• A filter is a tool that lets you view records that match a given criteria.

• Filters are helpful when searching for certain types of information in a large database with many records.

• A form can work with a filter, but enables you to view information about a single record.

Sorting Records

• Sorting means arranging the records in a database.

• A DBMS enables you to sort records alphabeticaly, numericaly, and chronologicaly.

• You can sort records in ascending (A-Z) order or descending (Z-A) order.

Querying a Database

A query is a statement you define, which tels the DBMS to find records that match criteriayou specify.

Modern DMBS software provides built-in querying tools, based on one or more of the folowing languages:

• SQL

• Query by Example (QBE)

• Xbase

Generating Reports

• A report is a subset of information from a database, produced in printed form.

• You can generate the data for a report by using a query, filter, or other tools.

• Reports can be formated in a wide variety of ways.

Enterprise Software

•Enterprise software is a large-scale application based
on a DBMS, used by a large organization.

•Enterprise software can meet the needs of many
diferent users in diferent locations.

•In an enterprise, diferent users by have diferent
interfaces to the database, so they can work only with
the data they need.

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