Everyone knows that computer usage can be tracked. However, depending on the browser, before you begin, you can hit "ctrl-shift-p" on Internet Explorer for "In Private" browsing, or "crtl-shift-n" on Google Chrome, for "Incognito" browsing. I imagine they have similar codes for Firefox, Opera, and other browsers.
If someone really wants in to your computer, they'll get in, but this might give you a bit more privacy when you are on line.
Drawscore