In most computer-based web browsers, to open menus used to clear your cache, cookies, and history, press Ctrl-Shift-Delete (Windows). If this doesn't work, follow the appropriate instructions for your browser using this web tool at RefreshYourCache.com.
A cache is temporary storage of data such as photos in your web browser that enables previously visited websites to load faster. This prevents you from having to re-download all of the data every time you visit the site.
An cookie is a small piece of data sent by a website that contains your preferences and settings for that particular website. This is how a website "remembers" you when you visit it again.
Browser history refers to the list of web pages you have visited recently which is recorded by your web browser for a certain period of time.