Computer Basics

Computer

Typically, a computer consists of a monitor, a CPU, a keyboard, a mouse and a speaker setup.
The monitor is the output screen. It gives visual communication.
The CPU, central processing unit is responsible for the entire task given to the computer. Stores information, performs arithmetic and logical calculation boot or start the computer. It consists of a boot or starts the computer. It consists of a power controller, mother board, bios chip, hard disk, CD-drive, FD-drive, etc.
Keyboard is the input device which contains control keys, alphabet and number keys. Also have special keys. Through this we can type information and do calculations.
Using mouse, we can place cursor at any point on the screen, and can have a control over that.
Speaker provides sound effects.

UPS [Uninterrupted Power Supply]

When power supply gets off while working computer, there can be chance of losing data. In such cases, the UPS saves the power and will provide to computer for 20 to 30 min. During this time we can store the data and safely shut down the system.

Registered Jack (RJ)

A type of connector, most often used in telecommunications.
RJ11 is a four or six pin connector used in most connections destined for voice use; it is the connector used on phone cards.
RJ45 is the eight pin connector used for data transmission over twisted-pair wiring and can used for networking. RJ45 is the connector used on 10BaseT Ethernet cables.

IP address

A unique 32 bit address, each machine must have in order to communicate on a TCP/IP n/w. This address is in the form x.x.x.x where x is a number from 0 to 255. Eg. 61.1.205.185

TCP/IP

- Transmission Control Protocol/Internet Protocol.
- A set of networking protocols widely used on the internet that provides communications across interconnected networks of computers with diverse H/W architectures and various operating systems.

BIOS

- Is a S/W routine that test H/W at startup, start the operating system, and support the transfer of data among H/W devices. The BIOS is stored in read-only memory. Although critical to performance, the BIOS is usually invisible to computer users.
- ROM-based software on a motherboard that acts as a kind of interpreter b/w an operating system and a computer's H/W.

POST.

A set of diagnostic programs, loaded automatically from ROM BIOS during startup, designed to ensure that the major system components are present and operating. If a problem is found, the POST S/W writes an error message on the screen, sometimes with a diagnostic code number including the type of fault located. These POST tests execute before any attempt is made to load the O.S [Operating System].

PING [Packet Internet Grouper].

A utility used to send a short message to another computer on a TCP/IP N/W. PING can be useful to test connectivity b/w N/Ws or to see if a particular machine is communicating with the N/W.

Port.

A connection point on your computer where you can connect devices that pass data into and out of a computer. For example, a printer is typically connected to a parallel port (also called an LPT Port) and a modem is typically connected to a serial port (also called com port).

USB

It is an external bus that supports plug and play installation. Using USB, we can connect and disconnect devices without shutting down or restarting the computer. We can use a single USB port to connect up to 127 peripheral devices, including speakers, telephones, CD-ROM drives, joystick, tape drives, keyboards, scanners, and cameras.
A USB port is usually located on the back of your computer near the serial port or parallel port.

Plug and play.

A set of specifications developed by Intel that allows a computer to automatically detect and configure a device and install the appropriate device drivers.

Non-plug and play.

A device, such as printer, modem, or game controller, that requires manual configuration of hardware settings before it can be used. No n-plug and play devices are becoming increasingly rare as manufacturers stop producing them in favor of plug and play devices.

Driver.

A program that allows a specific devices, such as a modem, n/w adapter, or printer, to communicate with the operating system. Although a device might be installed on your system, windows cannot use the device until you have installed and configured the appropriate driver.
If a device is listed in the Hardware Compatibility List (HCL), a driver is usually included with windows. Device drivers load automatically when a computer is started and thereafter run invisibly.

ISP (Internet Service Provider)

A company that provides internet access and e mail addresses for users. Generally, ISPs are local or regional companies

Routers.

A network node connected to two or more networks that forwards packets from one network to another.

CMOS.

PC has to keep certain settings when it's turned off and its power cord is unplugged. Some of these settings include: date, time, hard drive configuration and memory. PC keeps these settings in a special memory chip called the complementary metal-oxide semi-conductor chip.
When we shut off a computer anything that is left in main memory is lost forever. To prevent CMOS from losing its information, Mother Board manufacturers include a small battery, called the CMOS battery to power the CMOS memory.

Modem.

A modem is a device that converts digital signals, from a computer, into anolog signals for transmission over telephone lines. A modem also converts incoming analog signals into digital signals.

DSL.

DSL is a type of high-speed Internet access for consumers. DSL stands for Digital Subscriber Line. This is a technology that allows for digital transmission over existing telephone lines.DSL provide faster internet service while allowing regular phone/voice usage simultaneously on the same telephone line.

Cable modem.

Cable modem service is a type of high-speed Internet access offered by local cable companies for consumers, using the same coaxial cable used for TV signals..

LAN - Local Area Network

A network based on any physical network technology that is designed to span distance of upto a few thousand meters.

TCP/IP.

The TCP/IP protocol suite is the protocol architecture of the internet.
The TCP/IP suite has four layers.They are Application, Transport, Network, and Datalink layer.
Functions Of Layers Services Functions
Datalink Reliable transfer of frames over link, media access control on a link. Framing, media access control, error checking
Network Move packets from source host to destination host. Routing, addressing
Transport Delivery of data between host Connection establishment, error control, flow control
Application Delivery of email, retrieval of HTML documents, reliable transfer of file Application specific


Operating system
windows xp

Using Backup

The backup utility helps you to create a copy of the information on your hard disk. In the event that the original data on your hard disk is accidentally erased or overwritten, or becomes inaccessible because of a hard disk malfunction, you can use the copy to restore your lost or damaged data.
To start Backup, click start, point to Accessories, point to System Tools, and then click Backup.


Using System Information

System Information collects and displays your system configuration information. Support technicians require specific information about your computer so they can resolve your system problem. You can use System Information to quickly find the data they need.
To open System Information, click start, and then click Run. In the Open box, type msinfo32.exe.

Using Disk Defragmenter

The process of rewriting parts of a file to contiguous sectors on a hard disk to increase the speed of access and retrieval.
To open Disk Defragmenter, click Start, and then point to All Programs,point to Accessories, point to System Tools, and then click Defragmenter.

Using Device Manager

Device manager provides you with information about how the hardware on your computer is installed and configured, and how the hardware interacts with your computer's program.
With deice manager, you can update, disable, or uninstall the device driver for hardware installed on your computer, modify hardware settings, and troubleshoot problems.
Click Start, and then click Control Panel. Double-click System. On the Hardware tab, click device manager.

Using Disk Cleanup

Disk Cleanup helps free up space on your hard drive. Disk Cleanup searches your drive, and then shows you temporary files, Internet cache files, and unnecessary program files that you can safely delete. You can direct Disk Cleanup to delete some or all of those files.
To open Disk Cleanup, Click Start, and then point to All Programs,point to Accessories, point to System Tools, and then click Disk Cleanup.

Using System Restore

System Restore is a component of Windows XP Professional that you can use to restore your computer to a previous state, if a problem occurs, without losing your personal data files (such as Microsoft Word documents, browsing history, drawings, favorites, or e-mail). System Restore monitors changes to the system and some application files, and it automatically creates easily identified restore points. These restore points allow you to revert the system to a previous time. They are created daily and at the time of significant system events (such as when an application or driver is installed). You can also create and name your own restore points at any time.
To open System Restore, Click Start, and then point to All Programs,point to Accessories, point to System Tools, and then click System Restore.