3-D glasses were glasses usually made out of cardboard, and two transparent colored wax paper lenses, usually red and blue respectively, for use in watching three-dimensional movies. These were made to increase business of movies after the rise of television caused many customers to switch to this medium instead.
Thousands of movie theaters closed up shop in the 1950s. Although many 3-D movies of the 1950s were low budget "creature features", one noteworthy movie was shot in 3-D, House of Wax, which was medium-budget and intended for a more mainstream audience. Part of the reason for the lukewarm reception of Alfred Hitchcock's The Birds was that Hitchcock filmed it using special three-dimensional cameras, but by the time the movie was released, 3-D was largely out of style.
Managers of movie theaters would distribute the glasses to customers before the movie, then collect them after the customers left. Men who worked as theater attendants during this era often stated that the distribution and collection of the 3-D glasses was the worst part of their job, and it was easy for punks to simply walk away with the glasses without returning them — which is most likely how 3-D, one of Biff Tannen's gang in 1955, acquired the glasses he always wore for his trademark nickname. By 1985A, 3-D had customized his aviator glasses to contain red and blue lenses.
The 3-D movie fad largely passed by the 1960s, when by that era there was significant improvement in cinematography to attract moviegoers. It should be noted that by 2015, 3-D movies made a comeback, and were advanced enough that glasses were not needed to enjoy the show.