Web archives

MHTML, an initialism of "MIME encapsulation of aggregate HTML documents", is a web archiving file format used to combine, in a single computer file, the HTML code and its companion resources (such as images) that are represented by external hyperlinks in the web page's HTML code. The content of an MHTML file is encoded using the same techniques that were first developed for HTML email messages, using the MIME content type multipart/related. MHTML files use an .mhtml or .mht filename extension.

file format that specifies a method for combining multiple digital resources into an aggregate archival file together with related information

legacy compressed Zip file format