Caching is a technique used to improve the performance of a website or web application by storing the output of time-consuming tasks and reusing that output if it becomes necessary to generate the same information again.
Caching helps reduce load on a server. A cached copy of an online page can be fetched from the browser cache instead of being regenerated by the server, improving performance.
How Does Caching Work?
When a browser requests a webpage from a server, it sends along an HTTP header that includes a Cache-Control directive. The response from the server includes this same HTTP header with its own Cache-Control directive, which tells the browser how long to keep the page in its cache before using it again.