RFCs or Request for Comments, is the way that the internet develops standards. Read this to learn more: https://www.lifewire.com/what-is-internet-request-for-comments-rfc-4092366

Now the important thing is how to read an RFC.

  1. Is this an official RFC? What RFC did it update?
  2. What does this RFC give guidance on how to do?
  3. What are the 5 families of response status codes?
  4. What is a GET request and what does it look like?
  5. What is a User-Agent?
  6. What RFC guides "cache-control" in a header?