The parts of a computer you can touch, such as the monitor or the Central Processing Unit (CPU) are hardware. All hardware except the CPU and the working memory are called peripherals. Computer programs are software. The operating system (OS) is software that controls the hardware. Most computers run the Microsoft Windows OS. NacOS and Linux are other operating systems.
The CPU controls how fast the computer processes data, or information. We measure its speed in megahertz (MHz) or gigahertz (GHz). The higher the speed of the CPU, the faster the computer will run. You can type letters and play computer games with a 500 MHz CPU. Watching movies on the Internet needs a faster CPU and a modem.
We measure the Random Access Memory (RAM) of the computer in megabytes (MB). RAM controls the performance of the computer when it is working and moves data to and from the CPU. Programs with a lot of graphics need a large RAM to run well. The hard disk stores data and software programs. We measure the size of the hard disk in gigabytes (GB)
Computer technology changes fast, but a desktop PC (PERSONAL Computer) usually has a tower, a separate monitor, a keyboard and a mouse. The CPU, modem, CD-ROM and floppy disk drives are usually inside the tower. A notebook is a portable computer with all these components inside one small unit. Notebooks have a screen, not a monitor, and are usually more expensive than desktop with similar specifications
The desktop is the screen that appears after you boot up, or turn on, your computer. It shows a number of icons on a background picture or colour. When you buy a new computer and boot up for the first time, the desktop will only show a small number of icons. In the Windows operating system, these usually include My Computer and the Recycle Bin.
Double-clicking on an icon with the mouse opens a computer program, a folder or a file. Folders usually contain other files. You can move icons around the desktop, add the new ones or remove them by deleting them. Deleted files go the Recycle Bin. People usually put the programs they use most often on the desktop to find them quickly.
When you double–click on My Computer another screen appears. This screen shows the A: drive icon, for floppy disk; the C: drive icon, which usually contains all of the main programs and folders on your computer, the D: drive icon, which is usually the CD-ROM drive, and the Control Panel Folder.
When you double–click on Control Panel, another screen appears that shows many other icons, such as the Display icon and the Date/Time icon. Double-clicking on Display icon opens a box the lets you personalize your desktop by changing the screen saver (the moving image that appears when no one is using the computer) or the background picture.
Word processing: for and against
People use word processors for writing all kinds of documents, such as letters, school papers and reports. Word processors have many advantages over handwriting and manual typewriters. Word processing is faster and easier than writing by hand and you can store documents on your computer, which you cannot usually do on a typewriter. This makes it easier to review and rewrite your documents. You have more formatting choices with a word processors\, and the spelling grammar and language tools are useful, too. You can also print copies of your documents which look neater than handwritten ones. Many language students use word processors to improve their writing skills and because the help them feel proud of their work.
Word processors do have disadvantages, however. First, it is not easy to read long documents on a computer screen. Second, sometimes the printer does not print an exact copy of what you see on the screen. Not all word processors can read each other’s files, which is another disadvantage. Finally, word processors do not always work well with e-mail. If you paste a word-processed letter into an e-mail it may lose a lot of its formatting. Many people use a text editor for the Internet, which is similar to a word processor but has a fewer formatting features and cannot use graphics. Text editors, such Notepad, use a simple coding system called ASCII (American Standard Code of International Interchange), as does e-mail.