Grid Systems Corporation (stylized as GRiD) was an early portable computer manufacturer, based in the United States and oriented for the production of rugged and semi-rugged machines.

Grid Systems Corporation was founded in late 1979 by John Ellenby,[1] who left his job at Xerox PARC and joined Glenn Edens, Dave Paulsen and Bill Moggridge to form one of Silicon Valley's first stealth companies.

[4] Grid still produced the GRiDCASE laptops, and the first GridPad tablet also was released in 1989;[5] Also a few rebranded models of another manufacturers were released, include Tandy/Victor Technologies Grid 386 (Compaq SLT clone), GRiDPad SL 2050 (Samsung PenMaster clone) and AST GRiDPad 2390 (Casio Zoomer/ Tandy Z-PDA clone).

Edens co-founded Waveform Corp and in 2003 joined the board of F5,[6] and John Ellenby went on to co-found the companies Agilis and augmented reality pioneer GeoVector.

It had 256k RAM, an 8086, 320x240 screen, and 384k of internal 'bubble memory' that held data with power off.