Prototype of the first handheld electronic calculator

In 1967 Texas Instruments engineers Jerry Merryman, James Van Tassel, and Jack Kilby built a prototype of the first handheld electronic calculator at TI research facilities in Dallas. The prototype combined integrated circuits, a keypad, and a display into a portable device and directly led to Texas Instruments' commercial handheld calculators in the early 1970s. The development is documented in TI company histories and patents associated with the Dallas laboratories.