Short answers, pulled from the story.
Konami was founded on the 21st of March 1969 in Toyonaka, Osaka, as a jukebox rental and repair business. The company was started by three founders whose names were combined to form the name Konami. It transitioned into arcade game manufacturing in 1973 as the Japanese jukebox industry declined.
The Konami cheat code is a sequence traditionally embedded in Konami's games that grants power-ups to the player. It became one of the most recognized cheat codes in gaming history and has appeared across many of Konami's video game franchises.
Hideo Kojima left Konami in 2015 following a reported internal clash between Kojima and company leadership. Konami announced on the 3rd of March 2015 that it was restructuring away from individual studios, including Kojima Productions. After Konami prevented Kojima from accepting the Best Action-Adventure award at The Game Awards 2015 for Metal Gear Solid V: The Phantom Pain, he left and reopened Kojima Productions as an independent studio.
Silent Hills was cancelled in April 2015 without explanation from Konami, despite the widespread critical acclaim of its playable teaser P.T. Co-director Guillermo del Toro publicly criticized the cancellation, describing Konami's approach as "scorched earth" and stating it made no sense. Del Toro said afterward that he would not work on another video game.
Konami owns franchises including Metal Gear, Silent Hill, Castlevania, Contra, Frogger, Gradius, Suikoden, Tokimeki Memorial, and eFootball. Through its Bemani brand it publishes Dance Dance Revolution and Beatmania IIDX. It also publishes the Yu-Gi-Oh! Trading Card Game and owns the assets of Hudson Soft, which include Bomberman, Adventure Island, Bonk, Bloody Roar, and Star Soldier.
The Nikkei reported in August 2015 and again in June 2017 that Konami made it difficult for former employees to find other work, reportedly forbidding them from listing their Konami experience on resumes. Konami filed complaints against companies that hired ex-employees and, according to a former employee, sent legal letters threatening court action against those who spoke to the media. The company also pressured at least one former employee into closing a new business.