Blit
Bell Labs' 1982 graphical terminal, offering multiple windows onto one Unix host and running programs downloaded into the terminal itself.
Rob Pike and Bart Locanthi built the Blit around a Motorola 68000 and a portrait monochrome display of 800×1024 pixels. The name came from bitblt, the rectangle-copying operation all its drawing rested on. It hung off a Unix machine on an ordinary serial line, and the layers system carved the screen into overlapping windows, each with its own shell.
The clever part was that programs could be downloaded and run inside the terminal, so the text editor handled the mouse locally while the file stayed on the host. Teletype sold a successor as the AT&T 5620 DMD from 1984. The legacy is clearest in Plan 9, where Pike carried the same ideas forward.