Hardware, Software and Information Technology
The term hardware refers to the physical components of your computer such as the system unit, mouse, keyboard, monitor etc
The software is the collection of instructions which makes the computer work. For instance, when you type in words via the keyboard, the software is responsible for displaying the correct letters, in the correct place on the screen. Software is held either on your computer's hard disk, CD-ROM, DVD or on a diskette (floppy disk) and is loaded (i.e. copied) from the disk into the computers RAM (Random Access Memory), as and when required.
Information Technology (IT)
This is a general term which relates to the use of computers as an aid to creating and maintaining data, i.e. information. IT is related to all aspects of managing and processing information, especially within a large organization. Computers are critical to managing information, and computer departments within large organizations are often called IT departments. Alternative phrases are IS departments (Information Services) or MIS departments (Management Information Services). People working with computers within large companies will often refer to their job, as "working in IT".
Types of Computer
They are the big, powerful, expensive computers used in the background by most large organizations typically used to run the operations of an entire department or company
They are computers that fit on an individual desktop, but they might not have much storage capacity. Instead, they rely on devices elsewhere on the network to store information for them.
PC (Personal Computer)
They ware invented by IBM in 1981 it is computers that fit on or under an individual desktop and that store their own information this type is probably the type of computer that you're most familiar with
The Apple Mac is a computer, but NOT a PC. It uses a different operating system, and requires special versions of application programs (such as word-processors or spreadsheets). Even the hardware add-ons have to be customized to some extent to be able to be connected to a Mac
They are portable computers ranging in size from a briefcase to a small notepad they typically fold up to protect their screens when not in use
Personal Digital Assistants (PDAs)
They are very small computers that fit in a shirt pocket. They have limited storage capacity and screen sizes these devices use a special pen, rather than a keyboard and can be used for storing and retrieving information and can connect to the Internet
Comparing Computer Types
IT departments at major corporations
Home and business users
Business users who travel frequently
Professionals who need information "on the go"