Computer systems and their review | Lesson 2

Computer systems and their review | Lesson 2

Reviewing a digital computer system we see. The main processing device of the computer is the CPU. the two main input devices are the keyboard and mouse, the output devices are the monitor, printer and sound box.

Lesson 1 - Computer Generation Review And Use Of Systems

Central Processing Unit or CPU :

CPU The most important part of a digital computer system. It can be divided into three parts. 

• Memory unit
• Control unit
• Arithmetic and logic unit

Input Unit :

● Keyboard :

The main input device of a computer is the keyboard. Keyboard keys can be divided into four categories. Alpha-numeric keys, function keys, special keys and cursor movement keys.

● Mouse (Mouse) :

The mouse is currently a major input device in computers used in the Windows operating system. Mouse looks oval. Below it is a rubber ball. Currently the mouse is controlled by a laser beam instead of a ball. Those called optical mouse.

Storage Unit :

● Hard-Disk :

The main storage device of the computer is the hard-disk. The device is permanently embedded inside the CPU. A hard disk is a type of magnetic disk. Currently 40 GB, 80 GB, 120 GB. Hard-disks are available with capacities up to 320 GB, 512 GB, 1 Terabite.

● Floppy Disk :

Floppy disk is an important data portable storage device. A floppy can store 1.44 MB of data.

● Compact Disk :

Compact disc or CD. It looks like a round thin disc. A CD can hold 700-750 MB of data.

Output Unit :

●  Monitor :

The most important and main output device of the computer is the monitor. Monitors are divided into two categories based on color variation. Namely- (1) Monochrome (2) Color monitor.

● Printer :

The text or image displayed on the monitor can be printed on paper with the help of a printer. Examples of different types of printers are - dot-matrix, laser, inkjet, thermal printers etc.

● Sound Box :

Sound box is an important output device of computer with which music or any kind of sound can be played.

Important computer devices or devices :

The motherboard and modem devices used in the computer are very important. Every device in the computer system is directly or indirectly connected to the motherboard. A modem is a device or device through which a computer can be connected to a telephone line to exchange information across the world through a network. At present, computers are connected to the Internet in offices, businesses, cybercafes, and homes modem is used to connect with.

● Use of Computer :

It is basic for a common man to use a computer

1) Turn on and off the computer properly.

2) Operate mouse and keyboard properly.

3) To operate various computer programs like MS-Paint, MS-Notepad, MS-Word etc. properly.

Method of turning on and off the computer :

To turn on the computer, the power on-off switch in the computer cabinet should be used. Again, to shut down the computer in the Windows operating system, we use the Shut Down option Using the mouse and keyboard

The mouse currently seen has three buttons. Left, Right and Scrool button. Left-clicking usually does more. This button can be used to open or close any application program. Click the right mouse button to perform special operations such as deleting or renaming something.

Use Of Mouse & Keyboard

By turning the wheel of the scrool button we can move to the top or bottom of the screen in special cases. 

Use of Keyboard :

Caps Lock, Shift, Delete, Escape, Tab, Control, Name Lock, End etc. keys can be used to perform special tasks on the computer.

How to start or stop programs in Windows operating system

If the program is on the desktop, the program can be directly launched by double-clicking the icon with the pointer. Or if the program is not on the desktop, moving the mouse pointer over Start Programs Accessories and selecting from the list of software that appears will open the program.

To close a program in the Windows operating system, first click on the File menu in the menu bar and click on Exit under it, then any program can be closed directly.

Special functions of computer :

Among the special tasks we perform through computers, the most notable tasks are – on computers. Have fun typing, drawing, calculating or playing games.

Typing a text on the computer :

Notepad is one of the most important typing software that we use to type any text on the computer.

To open the Notepad software, move the mouse pointer over Start Programs Accessories and click the mouse on Notepad in the list of Accessories to open the Notepad software. Then with the help of the cursor, you have to type any text or text in Notepad by keyboard. To save a file in notepad, you have to take the help of the Save option under the File menu. The main menus we work with in Notepad are File, Edit, Format etc. The typed part can be changed, modified, corrected etc. with the help of Edit menu. The main options in the Edit menu are (Undo, Cut, Paste, Copy, Delete, Select All, Find, Next, Replace) etc.

With the help of Format menu we can change the Font size, style etc.

MS Paint 

MS-Paint is a popular software for Windows operating system.

Using we can draw different types of pictures with the help of mouse.

The different types of tools in MS Paint are :

Free from Select, Select, Eraser, Pencil, Brush, Text, Line, Curve, Rectangle, Polygon, Ellipse etc.

To work in ms-paint we take the help of the menus under the File menu – New Open, Save, Save As  Page setup Set as Background, Wallpaper, Exit etc 

Menus that belong to the Edit menu are Undo, Repeat, Cut, Copy, Paste, Clear, Selection, Select All etc.

Calculator :

In today's era, calculators have long been an important tool in every field from business to education .

being used as We can also do various calculations using the calculator on the computer. To bring the calculator on the computer screen, click Start Programs Accessories → Calculator with the help of the mouse.

With the help of calculator we can do addition, subtraction, multiplication and division and other complex mathematical operations. The calculator's memory button can be used to store any information.

Computer Games : 

Currently, computer games have become essential for entertainment and enjoyable time for everyone, young and old, through computers.