That is a Digital Equipment Corporation VT100, introduced in 1978.

It’s technically a video terminal, not a complete standalone computer though.

The VT100 connected through a serial cable to a larger computer, often a DEC PDP or VAX system. The larger machine stored files and ran programs, while the VT100 provided the keyboard and screen.

That keyboard looks like my Atari 800XL that I got for Christmas when I was a teen. Best. Christmas. Ever. Now I gotta find vintage Atari stuff to post.