Caching - why it's important, and why it's a pain in the article.
Everything on the internet is all about speed. How fast a page can be delivered to you, how fast an image or a video is shown. This is where caching can help, but also caching can cause problems with content, freshness, updates, and administration.
To understand about caching, you need to first understand how content is delivered to a visitor on a website
Without caching, a visitor will enter or click through to your website: