What computers can and can’t do

A computer is an electronic machine that stores and manipulates information (data). It does this by following specific instructions. These instructions are called programs or software. It can process and store large amounts of data very quickly. A computer seems to be able to do lots more than this. You may see pictures, text, or video and hear sound, but all the computer sees is numbers.
If you wanted to give the computer specific instructions to follow, you’d have to write a program for it to follow. These programs are written in one of many computer languages such as C++, Visual Basic or HTML. Someone who writes programs is called a programmer.

Computers require both hardware and software in order to work. 
Hardware. Hardware is the physical parts of the computer like the monitor, keyboard, mouse, speakers, and of course the computer itself called the system unit. Hardware is also the parts inside the system unit that you can’t see unless you open it up. Parts like the motherboard, RAM, and modem. Many hardware devices can be attached to a system unit to expand its capabilities, such as a speaker, scanner or printer.

Software. Software is the instructions given to the computer that tells it what to do. A computer cannot do anything without instructions. A computer must first read instructions before it can start to work. These instructions are called operating system software. When a computer is turned on, the first thing it does is find and read its system software. This software tells the computer how to work; how to be a computer. Once a computer has done this and is “booted up” or ready to go, it can read other instructions called application software. This type of software tells the computer how to do a specific task with a user, like writing a report, playing a game, or creating a graph.

A computer can do anything. However, you need to program it to do anything.

Computers can save a large amount of data, but there is must be a sufficient hard disk.
Computers can change the function of typewriter in writing a letter or a novel if there is Microsoft Word program.
Computers can help people in a presentation. Microsoft Powerpoint could make the presentation in an interesting visual form.
Computers can also entertain people with some interesting games for instance. There is also a program to play songs.

Unfortunately, computers can’ think as a person does
Computers will never be able to think. That is, really think. Not now or ever.
What the computer is doing is merely a superficial imitation of human intelligence. It has been designed to obey certain simple commands, and then it has been provided with programs composed of those commands. Because of this, the computer has to obey those commands, but without any idea of what's happening.