I've adjusted the expiration tags on many of the files of my website (with .htaccess). As you know, this can create a tiny problem of a users browser not showing the most updated version of a website until the cached version of the file expires.
I began looking for a way to avoid this and then I remembered using CloudFlare some time ago. CloudFlare makes it possible to adjust these same tags but it also has a purge feature. What is 'purge' doing?
Purge is telling us to purge the files that CloudFlare has cached on your site. You can do for the whole site (purge cache) or purge by single file.