Details

Browser Cache (temporary Internet files):

It's always completely safe to delete all the items in the browser cache. The files here are simply temporary copies of the web pages you have visited recently. The worst thing that can happen is that you may have to wait a few seconds longer the next time you visit the web page, and since the web page has almost certainly changed in the meantime you'll probably have to wait for it to reload anyway.

Cookies:

Deleting cookies is almost always safe. The only exceptions are the cookies created by trusted websites containing genuinely useful information that make browsing the sites easier or more fun. Examples of this include the personalized products lists displayed when you contact Amazon or stored user names and passwords so that you don't need to remember them to log on (although this feature is also a security risk if other users have access to your computer).

Visited Sites:

Deleting the Visited Sites entries is also completely safe. This is just a list of websites that you have visited recently. In Microsoft® Internet Explorer the entries here are used for the autocomplete function and recent sites drop-down list in the browser's Address: field. You only need to keep it if you want to find recently-visited sites that you haven't added to your Favorites list yet. Deleting these entries prevents other users from seeing where you have been on the web.

Visited Sites: Differences between Internet Explorer, Opera and Netscape:

In Opera®, Netscape® and Mozilla deleting the Visited Sites entries also deletes the browser history. In Internet Explorer the situation is a little different. Here, in addition to Internet websites, the History folder also contains details of all the files, drives and other items you have accessed recently on your own computer and other computers on your local network using either MS Internet Explorer or the Windows® Explorer. (This is a direct result of the close integration between Internet Explorer and Microsoft® Windows, which has been the subject of a great deal of controversy over the last couple of years.)

Deleting the Windows® Explorer and Internet Explorer History Folder:

To delete the contents of the Windows® Explorer and Internet Explorer History folder you must select the Empty History Folder option in the Scan screen.

You can display the contents of the History folder by clicking on the History icon in Internet Explorer or Windows® Explorer. You should delete these entries with the Empty History Folder option if you don't want others to see this information on your computer!

Select the Cookies entry and check the settings for searching for cookies. Full explanations are provided on the screen. Deleting cookies is also safe, but you may want to exclude cookies of trusted sites so that you can continue to use the functionality they provide.

Select the Cache, History entry if you want to change the settings for clearing the Browser Cache and clearing the Broswer History (visited URLs). By default both options are activated.