The cache is used to store images and html documents for Web pages you have recently visited. It speeds up the loading of Web pages if you go back to a page you've already visited. The problem is that the amount of memory allocated for the cache is limited. If it is full and you go to a new Web site, it has to delete some of the existing files before it can save new ones. If Safari is loading games slowly or hanging up frequently, you may need to Clear is file cache.
To clear the cache, go to Home >Settings >Safari and scroll down until you see the Clear Cache button. Tap it and confirm your choice when the pop-up appears. This page also lets you clear out the history folder, which tracks the Web pages you've visited, as well as empty the cookies folder.