Each time you access a file through your web browser, the browser caches (or stores) it. This improves the speed your browser performs as because it doesn't reload when you revisit the page. However, you should periodically clear the cache to allow your browser to function more efficiently.
A browser's history is a log of sites that you visit.
Sometimes you may want to clear your cache, cookies or history manually for privacy reasons. This is especially important if you are using a computer in a public place (such as internet cafes, hotels and airport lounges) to access sites such as internet banking,
Below are some links to access information on how to do this depending on the browser you are using.