Computer and Motherboard Computer 

 A computer is programmable machine that receives input, stores, manipulate data, and provides output in a useful format.

Computer takes input from input devices and then compute in CPU and stores in memory and sends output to output devices. The most common device for input is the keyboard. When you type, you are putting information into the computer, which is known as input. The most common device for output is the monitor. These input output devices are connected through I/O Ports.

Figure 1.1 : Working of Computer


A computer system unit contains many parts. As shown in Figure 1.2(a) and Figure 1.2 (b).

Motherboard :

 The motherboard is the main circuit board of a computer. It is also known as the main board or system board. Typically, the motherboard contains the CPU, BIOS, memory, mass storage interfaces, serial and parallel ports, expansion slots, and all the controllers required to control standard peripheral devices, such as the display screen, keyboard, and disk drive. Collectively, all these chips that reside on the motherboard are known as the motherboard's chipset. The motherboard can be thought of as the "back bone" of the computer. 

Overview of Motherboard
    
Figure 1.2 (b) : Detailed Overview of Motherboard

CPU :

 The CPU is the central electronic chip that contains the processing power of the computer. Today, all CPUs are microprocessors. 

1. A microprocessor is a complete computer on a silicon chip. 
2. A microprocessor does all of the functions of a computer. 
  • stores data and instructions waiting to be used.
  • follows changeable instructions. 
  • does input, processing, and output.

Memory : 

Memory is the part of the computer that temporarily stores applications, documents, and system operating information.

I/0 Ports- 

In this sub-section, we will study about I/O ports.

Ports and Connectors : A port is a connector located on the motherboard or on a separate adapter. This we will discuss in following sub section.

As shown in figure 1.2 an internal view of some of the I/O ports. On the back of computers are several I/O (or Input/output) ports. Above, on the very top are two PS/2 ports, normally used for mouse and keyboard connections. Below that are the USB, (or Universal Serial Bus), ports. Below those are two serial ports beside a long parallel port that is often used to connect to a printer. On the bottom right is a game port for joysticks or other game controllers. On the bottom left is a microphone hook up, a speaker hook up, and an additional hook up for another sound input device like a musical keyboard. 

 I/O ports are there to connect to I/O devices. There are various I/O devices which are discussed in the next subsection:

I/O Devices

Few I/O devices are given Table 1.1.

Few I/O devices are given Table 1.1.

Here, we are discussing about Keyboard and mouse. Rest is kept for you to explore

Keyboard Basics 
Keyboard
  • is used to type data into the computer. 
  • is most common input device. 
  • has special keys for giving the computer commands. 
  • Commands tell the computer to do something, like save the file. 
  • These special keys are called command or function keys. 

    Types of Keys

Typing Keys / Main Typing Keypad: It holds alphabetic character such as letter, special characters and numbers for typing.     

Numeric Keypad: It can be used as numeric and directional keys, pressing the Num Lock key above the numeric keypad will tell whether the keys are on numeric or directional mode. If it is on, it is on numeric mode and can enter numbers. If it is off, it is on directional mode and only used for moving a cursor on screen UP, Down, Left or Right. 

Function Keys: There are 12 functions keys starting from F1 through F12. These keys are used for special purposes. 

Control Keys: It has two groups of keys, arranged from top to bottom.

The top keys holds Insert, Home, Page Up, Page Down, Delete, and End keys. Insert key switches between insert and overtype modes. Home key brings you back at the beginning of a page. Page Up and Page Down keys help you to move one page or screen up or down. Delete key erases a text or page. The End key takes you at the end of a page.

The bottom keys are independent directional keys, which let you to move the cursor Left, Right, Up and Down. Status lights, Escape key, Print Screen/SysRq, Scroll Lock, and Pause/Break are user for frequent functions. 

Status Lights : These light indicate whether Num Lock, Caps Lock or scroll Lock light is on /off.

There are several short cut keys to make our work convenient when mouse is not working or if we do not want to do several maneuvers with the mouse. It makes our work convenient while working with MS-Word. 



How keyboard connects to a computer?

Computer Keyboard can connect with a computer through a cable or signal (wireless connection). Until recently, a keyboard used to connect with the standard PS/2 type or Serial. 

Now, this trend has changed and the connection is replaced by USB (universal Operating System serial bus) and wireless connectors. Most modern PCs (motherboards) even don‘t have PS/2 connectors, only USB

Since, there is no cable connection with main PC, wireless keyboard gets power from battery or a/c power connection. This is the side effect of wireless keyboards; you often have to change battery. 

Mouse 

The mouse is a small device used to point to a particular place on the screen and select in order to perform one or more actions. It can be used to select menu commands, size windows, start programs etc. The most conventional kind of mouse has two buttons on top: the left one being used most frequently

Mouse buttons

Primary button / left button for left click Secondary button / right button for right click Scroll wheel for moving page up or down

Mouse Actions

Pointing : Point the object
Left Click: Used to select an item. 
Double Click: Used to start a program or open a file.
Right Click: Usually used to display a set of commands.
Drag and Drop: It allows you to select and move an item from one location to another. To achieve this place the cursor over an item on the screen, click the left mouse button and while holding the button down move the cursor to where you want to place the item, and then release it. 

How Mouse is connected to PC 

Mouse is connected to pc similarly as keyboard. It can be connected with either PS/2 connectors or USB. The connections can be through a cable or wirelessly as well.