The cache (pronounced "cash") is a space in your computer's hard drive and in RAM memory where your browser saves copies of previously visited websites. Your browser uses the cache like short-term memory. Instead of downloading an image from a recently viewed website, it will load the image from your cache folder, thereby making the browsing process a little bit quicker.
Clearing the cache just means emptying it, so that the next time you display a web page everything must be re-downloaded. Many times web developers have to make updates to files in order to push changes or a new features. If your browser has cached the previous version, it’s going to keep showing the old version of the site and you won’t see the most recent changes. That’s why it is important to clear your cache from time to time.
For detailed instructions on how to clear your cache from the most common browsers on the most common devices, please click here.