Caching is a technology related to memory management on computers, websites and servers.
To best understand the concept of caching, let’s take a look at a simple example using library books. Let’s say that you wanted to do a study of artwork in oversized books that you are not able to check out of the library. Without applying the principle of caching, you would drive to the library, find the books, make a few notes and then drive home. When you wanted to look at the books again, you would have to drive back to the library, find the books again, make more notes… you get the idea. So how does this get to be more efficient?
By applying a cache to this project, you would drive to the library once, find the books, make photocopies of the pictures and then drive home with your photocopies. You save all kinds of time if you want to see those same photographs again.
Caching works the same way on your browser
When you click on a website for the first time, it may take a couple of seconds for the page to load. This is like driving to the library and copying the photographs in our example above. Once the page loads, your browser caches and dates that page. Whenever you return to that page, your browser compares the date of the cached page with the date of that page on the internet. If the dates are the same, it will serve up the cached version.
There is caching on your computer, on your browser, and on websites themselves.
Now the real question – How does this affect my own website?
Google applies many factors in selecting which websites to return in search. If the search algorithms have determined your website is a contender in results, your site’s ranking will be measured against the rank of your competition. An important factor in rank is how fast your site loads. By enabling caching on your site, you can improve your chances of higher rank.