If you use internet explorer for a web browser, click on tools in your menu bar, then choose internet options. Under the general tab, you'll find the option to clear files and cookies. This simple cleans out your temp memory folder, note: if you use the "remember me" fuction to log into any sites, you will need to rekey in your passwords after doing this.
And as tailfeather stated about, you will find that this can speed up you computer quite a bit if you do this on a regular basis
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