Cache (pronounced cash) is vital to any website or web application. Cache can increase the speed of your websites and web apps. Having the right settings for your cache are imperative. Knowing the correct amount of time before clearing it on your server or allowing certain pages to be exempt from being cached all play a role in the overall performance of your site or app.
Web caches generally sit between the web server and the web browser. They act as like a middle man storing resources and files and serving them when the server is requested. Most modern browsers store a cache locally as well to help reduce the download time of websites. However this causes a need to ensure that your updated site is viewed by all too. So sometimes manually clearing your servers cache will assist.
Web browsers cache is usefully when they same image or logo is used in multiple places wishing your site or app; or when the user presses the back button, they no longer need to send the whole request back to the web server.
There is no way you can completely avoid the cache when browsing the web, so for web developers it is just best to befriend the cache and make it work for you in your designs to improve both speed and performance.
