I\u2019ve finally configured caching on my site. Here\u2019s what you need to know.<\/p>\n
There\u2019re 4 headers that enable caching: In practice, you choose 2 of these headers: one primary and one secondary \u2013 and use them together. Using all four headers isn\u2019t very practical \u2013 the browser will rely on only two of them.<\/p>\n I recommend choosing Cache-Control<\/code>\/Expires<\/code> and Last-Modified<\/code>\/ETag<\/code>. The former two are primary; they enable caching and instruct the browser on how long it should save a resource. The latter two are secondary and optional; browsers use them when the cached resource gets expired to check if it has changed. (If it hasn\u2019t, browsers just take the expired one and keeps using it.)<\/p>\nCache-Control<\/code> and ETag<\/code>. Cache-Control<\/code> lets you configure the caching details that Expires<\/code> can\u2019t. ETag<\/code>, according to MDN, is more reliable<\/a> than Last-Modified<\/code>.<\/p>\n