GRiDPad was a trademarked name for a series of pen computing tablets built by GRiD Systems Corporation.
The GRiDPad 1900, released in 1989, is regarded as the first commercially successful tablet computer. Jeff Hawkins went on to use the GRiDPad as a predecessor for his best known-invention, the Palm Pilot.
PalmPad | 2350/51/52 | NEC v20 (9.5 MHz) | 2–2.5 MB RAM | PCMCIA | 6.5", 640 × 400 B&W backlit | MSDOS 5.0, PenRight | 2.8 lb (1.3 kg), 9 x 6.25 x 1.9" (318 x 235 x 38 mm) | Mar 1992 | 1st Wearable; Wireless 902-928 spread spectrum radio on 2352 |