A computer is an electronic machine that changes input in the form of some result. A computer consists of hardware and software and available in different sizes and designs. Today, computer is used in each and every field whether it is an educational institution, hospital, home, business etc.

There are different types of computers: super computers or mainframe computers, personal computers, laptop computer and many more. Large companies generally use super computers. Small computers or PC's are meant for individual use. A laptop is also a small computer that can be easily transported and handled. The commonly used type of computer in these days is embedded computer that also control another devices.

A computer mainly consists of four main sections: Arithmetic and logic unit (ALU), control unit, memory unit and input and output devices. It is the important part of the CPU that performs various arithmetic and logical operations. The various input and output (I/O) devices are those through which a computer receives information and changes into the form of results. There are different I/O devices like keyboard, mouse, monitor, printers etc. A control unit controls the overall operations of a computer. The control unit is divided into two different parts: microcoded control units and hardware control units.

There are numerous companies that offer best computers for your service. It is very important to choose the best computer company. Some of the best companies are Dell, Compaq, E Machines, Gateway, Toshiba, HP and Midwest Micro.

You can also shop for computers online. You can also make price comparisons on PC's, laptops, notebook computers and other computer devices online. This can save your time and money and ease your confusion.