Enable Leverage browser caching for your website

So you are optimising your website and have most probably used the Google Page Speed Tool and/or the Pingdom page speed tool. Upon checking your site to see how its performing you come across this: Leverage browser caching. The tools you check with tell you to Enable Leverage browser caching for… – https://www.umbrella-host.co.uk/blog/enable-leverage-browser-caching-for-your-website/