web archive is a windows IE specific file format (.mht) .
it simply allows you to save a single web page as a single file (embeds
pics, etc.)
this format allows you to send a web page to someone as a single entity.
it is not something used for a web site!!
personally I use an .mht when I see a web page while online that I want to
save and look at later, in my browser I go to File, save as, save as file
type: .mht, Save to my documents. That way later I can view it from my drive
rather than going back online and finding it.