computer first aid

Glossary of some computer terms

Q. What is Safe Mode?

A. Safe mode usually boots up when there is a problem with a recently installed application or hardware driver. This stripped down version of Windows allows you to troubleshoot and fix what is causing the problem.

One of the most commonly asked things about safe mode is, why does it look so ugly? Well, safe mode basically boots in a safe way.

This safe boot means that certain things are not loaded. When it comes to the display, your normal graphics driver is not loaded, and your desktop loads in a color and resolution setting that is far from attractive.

Those of you that are curious about what happens when you boot into safe mode, and how you can fix problems in it, should visit this page:
http://www.howstuffworks.com/question575.htm

The page is a part of the Howstuffworks Web site. When you have questions about computing, take a look at this site:
http://www.howstuffworks.com/

Q: What is a zip file, and how do I open one?

A: Zip files can be found on many different sites around the Internet. You may have seen one of these files and downloaded it, but when attempting to run the file it does nothing.

First of all, zip files (often called archives) are single files that can contain one or more compressed files. The compression aspect of zip files really means a lot. Downloading large documents on the Internet can be a real pain when you are stuck with a dialup connection. A zip file, however, can greatly decrease the size of the download, and this makes it easier to e-mail to people or even post on the Web. Zip files are distributed on countless software Web sites because the format keeps the size practical and it provides one simple install file.

In order to open these archives (or create your own), you will need a compression utility. The most popular application for compression to date has to be WinZip, but there are any others.

Q. What is file fragmentation?

A. Sometimes when you install a program or create a data file, the file ends up chopped up into chunks and stored in multiple locations on the disk. This is called fragmentation.

What makes this happen?

When you first install your operating system and programs on your hard disk, they are written to the disk, for the most part, in one contiguous block without any gaps. The exceptions are certain system files that must be stored in specific locations. Over time, as you create and then delete documents or uninstall programs, once-filled locations are left empty and you end up with files dotted all over the disk.

Now, when Windows is writing a file to the disk, it looks for a suitable piece of free space in which to store it. What happens, then, when you copy a 40M database or audio file to the disk and the biggest slice of free space is only 30M? Or say you modify an existing file, appending a whole bunch of data so the file now takes up more space on the disk.

To accommodate the files, Windows writes the first part of the file in one section of the disk and then scouts around for other places to store the rest of the file. The end result is that a single file may be stored in several chunks scattered about the disk.

Did you know?

The way Windows organises files on a hard drive has a perceptible impact on the performance of your computer. If your files are stored neatly, end-to-end, without fragmentation, reading and writing to the disk is speedier. Windows comes with a collection of house cleaning tools, like Disk Defragmenter, to help keep your disk in peak working order. Click here to find out more about Disk Defragmentation

Q. What is CPU?

A. CPU stands for central processing unit. This is where all the computer's data processing is handled - all the data manipulation, calculations and formatting data for output.

Q. What is RAM?

A. RAM means "read access memory" (or sometimes "ready access memory"). It is like a temporary notepad where your computer sends information it has processed before writing it to disk, or where instructions from other input devices (keyboard, mouse floppy drive) are stored. The words "random access" indicate that memory locations in RAM are accessible in any order unlike sequential access of a data cassette tape, for example.

Q. What is an Operating System?

Every computer needs a set of programs called the operating system to run the system and make all the other programs work. Your word processor, database or spreadsheet programs can not operate unless the operating system is present. Programs written for one operating system will not work on a different operating system.

Common operating systems include: Windows (XP or Vista), Linux (there are many versions aimed at different uses) and Macintosh OSX.

Q. What does Booting mean?

The term "booting" refers to the start up of the computer and the loading of the required parts of the operating system into RAM. When the computer is first switched on:

  1. The permanent instructions residing in ROM start up. They test the machine to see that all the physically parts are present and working. BIOS information will be displayed on screen at this time (look for the rectangular box enclosed in double white lines).
  2. The computer then carries out a quick test of the machine’s memory locations (see the RAM ticking over on screen).
  3. Then the system will head to the hard disk drive or the C: drive and will start to load the operating system.
  4. It finds the system files command.com, io.sys, msdos.sys and loads them into RAM.
  5. If there are peripherals that windows does not recognise an autoexec.bat file will execute
  6. Windows then loads over the top of DOS (disk operating system

More information available at these links:

If you can't find what you're looking for try the Google Search below
Google