For many years, the optical transit was the surveyor’s tool of choice to lay out property lines and building sites. By the 1970s, however, the electronic theodolite began to replace the transit since it could measure angles more accurately on both the horizontal and vertical axes. In the early 1980s, "total stations," which measure distances very accurately by using electronic distance meters (EDMs), became the instrument of choice. Then in late 1990, Geodimeter, Dandryd Sweden introduced the first "robotic total station," adding automatic tracking and radio communication to a radio and data collector at the "target" or pole. Thus, for the first time, no person was required at the instrument—only at the target, reducing the size of a survey crew.