Basically a cookie is tracking device that gets stored on your computer after you visit a website usually cookies are harmless but they can also be used to track your browsing history.
Think of it this way, when you login to yahoo, there is the "remember me" option, if you select that and continue, you now have a cookie from yahoo telling them that you want to be remembered, so the next time you go to yahoo the cookie tells them them that since you selected that option you don't have to manually login because of the cookie tells them of your choice so you get logged in automatically in the background. But in two weeks the cookie expires, meaning that it is now defunct, and then you start the process all over again.
This is from Wikipedia: Cookies are also subject to a number of misconceptions, mostly based on the erroneous notion that they are computer programs. In fact, cookies are simple pieces of data unable to perform any operation by themselves. In particular, they are neither spyware nor viruses, despite the detection of cookies from certain sites by many anti-spyware products.
Most modern browsers allow users to decide whether to accept cookies, but rejection makes some websites unusable. For example, shopping carts implemented using cookies do not work if cookies are rejected.
http://en.wikipedia.org/wiki/HTTP_cookie
Download firefox it's way more secure the IE,
http://www.mozilla.com/en-US/firefox/. After you download firefox download Adblock
https://addons.mozilla.org/en-US/firefox… then download all of these, I guarantee you that your computer performance will be much better, I use all of these myself,.
1 Ad-Aware 2008, Much more effective than previous versions and faster, does not suck up system resources like the previous versions, also there various skins to suit your preferences.
http://www.download.com/Ad-Aware-2008/30…
2 Spybot - Search & Destroy, its a little out of date but it works.
http://www.download.com/Spybot-Search-De…
3 SpywareBlaster, blocks potentially damaging applications and programs from running.
http://www.download.com/SpywareBlaster/3…
4 Simple File Shredder, it isn't an anti spy, but it shreds unnecessary files including cookies and it speeds up system performance.
http://www.download.com/Simple-File-Shre…
5 MRU-Blaster, detects and cleans MRU (most recently used) lists on your computer. By looking at these MRU lists, someone could determine what files you opened/saved/looked at, what their file names were, and much more! (And, in many cases, the lists are displayed in drop-down menus automatically.) (From website.)
http://www.javacoolsoftware.com/mrublast…
I personally don't like AVG, it screwed up my computer after I Un-Installed it, and avast didn't work for me.
Hope this explained what a cookie is, what it does. and I hope the anti-virus programs help you.
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