For the best results, and to optimise computer performance and efficiency, it's best to eliminate the many temporary files and temporary Internet files that build up on one's hard disk over time.

Temporary Internet Files result simply from visiting web sites. Each web page usually consists of a number of individual elements, including one or more images. A typical business page is made from a large number of individual images, even if only a single image is visible when the page is fully loaded. Each of these images is stored on your hard disk in the Temporary Internet Files folder, also known as the Internet Cache". Other elements such as cookies and multimedia files are also stored here. Particularly useful in the early days of the Internet when only dial-up accounts were available, the use of this cache idea helped speed up access to web pages on the second and subsequent visit. Because images and multimedia objects take a lot longer to download than text, once they were stored in a local cache, they would be displayed directly from the hard disk, and didn't need to be downloaded again. Web access was therefore a lot faster. There appears no way of automatically deleting these files, and so the number increases constantly.

Temporary Files appear for other reasons. In the course of normal operation by some programs, they require “working space" and will create one or more temporary files. When programs are installed, particularly from zipped or compressed files, they usually need a temporary storage area in which to store files during the installation process. It would make sense in both these cases, for the programs to delete the temporary files when finished. However, it seems that in a lot of cases, the obvious doesn't happen.

Why should we care that we have all these unwanted files on our hard disks?

Firstly, they do take up disk space unnecessarily, and secondly they reduce the performance of our computers. But in the context of viruses, spyware, adware, malware and other nasties, there are two reasons why all these temporary files are unwanted.

Most of the “nasties" mentioned above, apart from viruses, infiltrate our computers whilst visiting websites. Objects downloaded from web sites sit on our hard disk in the Temporary Internet Files folder. Deleting these files, therefore, is the first step to eliminating nasties. Some viruses and nasties will install themselves, or a copy of themselves in the Temporary folder where no-one can find them. Have you ever run a virus or spyware scan only to find that the culprit comes right back afterwards? The other reason to delete these files ... and there could be a great many of them over time ... is to minimise the time the scanning software has to run by reducing the number of files it has to scan.

Fortunately, Windows gives us a simple method to delete these files.

Click on “Start" and “My Computer". With the right mouse button, click on your primary hard disk, usually the C: drive, known in Windows XP as Local Disk (C:). In the menu that opens, click on the “Properties" selection at the bottom. The window that opens will display a graphically representation of your hard disk showing the total space, and the amount used and free. On the left is a button called “Disk Cleanup". Press that button.

Windows will now check your hard disk and open another window showing how many temporary and temporary Internet files there are. If you click on “ok", Windows will proceed to delete those files. It's safe to do so. The recycle bin is also listed, and if you haven't emptied it for a while, now is a good time to do so. Leave the other options unchecked.

Your virus scanning software and “anti-nasties" programs will now run more quickly, and in fact, you might find your whole computer seems faster and more responsive.

There is one limitation of the Windows built-in file cleaner though: it often doesn't delete all files, and the only way of doing it is to manually delete them. That'll be covered in a future article.