The gps (jan 1, 1990 – sep 24, 1992)
Description:
In 1995 was when the gps was first optional. It was made by Ivan A. Getting, Roger L. Easton,and Bradford Parkinson. But it first became public in 2000.
Added to timeline:
Date:
jan 1, 1990
sep 24, 1992
~ 2 years and 8 months