This year, the Rubik's Cube — that 3D puzzle that frustrates nearly everyone who picks one up — is celebrating its 40th birthday.
Hungarian Prof. Erno Rubik created the brainteaser in 1974 as a way to engage his students and give them an interesting task. Manufacturers didn't immediately jump on his design, but once it hit shelves it was a colossal success: 300 million have sold over the past 40 years. "It was a dream," Rubik told NBC News. "And in three years we sold out more than 100 million. ... I have called it magic, because for me it was really magic. That's my cube."
Check out a retro NBC News clip below on the Rubik's Cube (dubbed "a maddening addiction"), featuring an interview with Rubik and what it was like manufacturing the toy in then-Communist Hungary. --Catherine Garcia