What is Computer?

Computer is a programmable machine. This means it can execute a programmed list of instructions and respond to new instructions that it is given. Today, however, the term is most often used to refer to the desktop and laptop computers that most people use. When referring to a desktop model, the term "computer" technically only refers to the computer itself -- not the monitor, keyboard, and mouse. Still, it is acceptable to refer to everything together as the computer. If you want to be really technical, the box that holds the computer is called the "system unit."

Some of the major parts of a personal computer (or PC) include the motherboard, CPU, memory (or RAM), hard drive, and video card. While personal computers are by far the most common type of computers today, there are several other types of computers. For example, a "minicomputer" is a powerful computer that can support many users at once. A "mainframe" is a large, high-powered computer that can perform billions of calculations from multiple sources at one time. Finally, a "supercomputer" is a machine that can process billions of instructions a second and is used to calculate extremely complex calculations.

 It has two principles. These are: 1. It responds to a specific set of instructions in a well-defined manner. 2. It can execute a prerecorded list of instructions (a program). Modern computers are electronic and digital. The actual machinery -- wires, transistors, and circuits -- is called hardware; the instructions and data are called software.

Computers can be generally classified by size and power as follows:

Personal computer: A small, single-user computer based on a microprocessor. In addition to the microprocessor, a personal computer has a keyboard for entering data, a monitor for displaying information, and a storage device for saving data. 
Workstation: A powerful, single-user computer. A workstation is like a personal computer, but it has a more powerful microprocessor and a higher-quality monitor. 
Minicomputer: A multi-user computer capable of supporting from 10 to hundreds of users simultaneously. 
Mainframe: A powerful multi-user computer capable of supporting many hundreds or thousands of users simultaneously. 
Supercomputer: An extremely fast computer that can perform hundreds of millions of instructions per second.

All general-purpose computers require the following hardware components:

 
Memory: Enables a computer to store, at least temporarily, data and programs. 
Mass storage device: Allows a computer to permanently retain large amounts of data. Common mass storage devices include disk drives and tape drives. 
Input device: Usually a keyboard and mouse, the input device is the conduit through which data and instructions enter a computer. 
Output device: A display screen, printer, or other device that lets you see what the computer has accomplished. 
Central processing unit (CPU): The heart of the computer, this is the component that actually executes instructions. 
In addition to these components, many others make it possible for the basic components to work together efficiently. For example, every computer requires a bus that transmits data from one part of the computer to another. 

How do we communicate with the computer?

Only way we can communicate with the computer is with a "Keyboard" and "Mouse". Without the mouse and keyboard we couldn’t do any tasks on the computer. When we do a task on the computer we can see it on the screen so displayed on the computer. So the Screen is the output and input is the "keyboard" and "mouse"

AMU:
This is the hard drive of the computer it stands for Auxiliary Memory Units. This is why you can store data on your computer if this didn’t exist you couldn’t store anything at the computer. This can be called your root of the computer "C:"

Secondary AMU's:
This will go under the name CD room, Floppy disks, CD. This can be called secondary storage places on the computer. This are normally used to copy important information on so you don't want to loss. Why should I make a copy of important information? Well sometimes things can happen to the computer like the Auxiliary Memory Unit Crash. This will say that the hard disk won’t boot up. Or maybe you get Virus infection so is destroying your computer.  

How does the computer work?

Here we discuss about HOW DOES THE COMPUTER WORK. This will show you how the computer is build up how it works.

CPU:
This is the CPU stands for "Central Processing Unit" this is the brain to the computer. This is why you can run different programs at the same time. If you press "CTRL+ALT+DEL" you can take a look at the CPU. The job to the CPU is to run programs you want the computer to run. When you click on a program the RAM is getting the data to the CPU.

RAM:
This is the RAM stands for "Random Access Memory" this function work is to give the data to the CPU so that it can run a program. If you have a lot of RAM you start up the programs faster since they send more information faster to the CPU.