When IA first started doing their thing, they came across a problem: how do you actually save all of the information related to a website as it existed at a point in time? IA wanted to capture it all, including headers, images, stylesheets, etc.
After a lot of revision the smart folks there built a specification for a file format named WARC, for Web ARCive. The details aren’t super important, but the gist is that it will preserve everything, including headers, in a verifiable, indexed, checksumed format.
