Although Star Trek and Star Wars seems to be at the center of the media frenzy reporting the first tractor beam technology, they have long forgotten Buck Rogers (1939) that used a repeller beam against other spaceships to make their get away.
The tractor beam was a term used intermittently in science fiction sometimes called the antigrav(ity) beam, repeller beam or pressor beam. Most science fiction tied a force shield to the tractor beam wrapping itself around the object.
Today’s laser beams use light to attract microscopic objects. Martin N. Kaplan of Ryan Aeronautical in San Diego published an article in July of 1960 that discussed tractor beam theory in an effort to encourage funding for research. The article hypothesized that if successful, they would be able to direct anti-gravitational forces towards or away from a second body. Some believe it was this article that inspired the classic Star Trek laser beam.
Research continued for 60 years to bring us to current events announcing that man has been successful in developing a tractor beam that will work on the microscopic level in liquids and vacuums. The applications of this technology is limitless and have significant benefits in medicine such as separating white and red blood cells.
The challenge we face next in technology is to manage the transfer of energy. On a microscopic level the transfer of energy used in the laser beam technology is insignificant but would cause problems from the heat generated in a larger object.