Types of computers
Computers range in size and capability. At one end of the scale are supercomputers, very large computers with thousands of linked microprocessors that perform extremely complex calculations. At the other end are tiny computers embedded in cars, TVs, stereo systems, calculators, and appliances. These computers are built to perform a limited number of tasks.
The personal computer, or PC, is designed to be used by one person at a time. This section describes the various kinds of personal computers: desktops, laptops, handheld computers, and Tablet PCs.
Desktop computers are designed for use at a desk or table. They are typically larger and more powerful than other types of personal computers. Desktop computers are made up of separate components. The main component, called the system unit, is usually a rectangular case that sits on or underneath a desk. Other components, such as the monitor, mouse, and keyboard, connect to the system unit.
Laptop computers and small notebook PCs
Laptop computers are lightweight mobile PCs with a thin screen. Laptops can operate on batteries, so you can take them anywhere. Unlike desktops, laptops combine the CPU, screen, and keyboard in a single case. The screen folds down onto the keyboard when not in use.
Small notebook PCs (often referred to asmini-notebooks), are small, affordable laptops that are designed to perform a limited number of tasks. They’re usually less powerful than a laptop, so they’re used mainly to browse the web and check e‑mail.
A laptop computer and a small notebook PC
Smartphones are mobile phones that have some of the same capabilites as a computer. You can use a smartphone to make telephone calls, access the Internet, organize contact information, send e‑mail and text messages, play games, and take pictures. Smartphones usually have a keyboard and a large screen.
Handheld computers, also called personal digital assistants (PDAs), are battery-powered computers small enough to carry almost anywhere. Although not as powerful as desktops or laptops, handheld computers are useful for scheduling appointments, storing addresses and phone numbers, and playing games. Some have more advanced capabilities, such as making telephone calls or accessing the Internet. Instead of keyboards, handheld computers have touch screens that you use with your finger or a stylus (a pen-shaped pointing tool).
Tablet PCs are mobile PCs that combine features of laptops and handheld computers. Like laptops, they’re powerful and have a built-in screen. Like handheld computers, they allow you to write notes or draw pictures on the screen, usually with a tablet pen instead of a stylus. They can also convert your handwriting into typed text. Some Tablet PCs are “convertibles” with a screen that swivels and unfolds to reveal a keyboard underneath.
What can you do with computers?
In the workplace, many people use computers to keep records, analyze data, do research, and manage projects. At home, you can use computers to find information, store pictures and music, track finances, play games, and communicate with others—and those are just a few of the possibilities.
You can also use your computer to connect to the Internet, a network that links computers around the world. Internet access is available for a monthly fee in most urban areas, and increasingly, in less populated areas. With Internet access, you can communicate with people all over the world and find a vast amount of information.
Here are some of the most popular things to do with computers:
The World Wide Web (usually called the web, or web) is a gigantic storehouse of information. The web is the most popular part of the Internet, partly because it displays most information in a visually appealing format. Headlines, text, and pictures can be combined on a single webpage—much like a page in a magazine—along with sounds and animation. A website is a collection of interconnected webpages. The web contains millions of websites and billions of webpages.
Example of a webpage (Microsoft Game Studios)
Surfing the web means exploring it. You can find information on the web about almost any topic imaginable. For example, you can read news stories and movie reviews, check airline schedules, see street maps, get the weather forecast for your city, or research a health condition. Most companies, agencies, museums, and libraries have websites with information about their products, services, or collections. Reference sources, such as dictionaries and encyclopedias, are also widely available.
The web is also a shopper’s delight. You can browse and purchase products—books, music, toys, clothing, electronics, and much more—at the websites of major retailers. You can also buy and sell used items through websites that use auction-style bidding.
E‑mail (short for electronic mail) is a convenient way to communicate with others. When you send an e‑mail message, it arrives almost instantly in the recipient’s e‑mail inbox. You can send e‑mail to many people simultaneously, and you can save, print, and forward e‑mail to others. You can send almost any type of file in an e‑mail message, including documents, pictures, and music files. And with e‑mail, you don’t need a postage stamp!