.edu is EDU Internet domain
Key Features: .EDU File Extension
What is an .EDU file?
The EDU is not a file extension, but it is used as top-level domain that means education.
EDU is the sponsored top-level domain (sTLD) in the Domain Name System of the Internet for educational institutions, primarily those in the United States.
Although not officially mandated for much of the domain's existence, in practice it has been used primarily for U.S.-based four-year universities.
Starting in 2001, it was officially restricted to accredited postsecondary institutions and organizations that are accredited by nationally recognized accrediting agencies.