Doom (1993 video game)
Because id planned to self-publish the game, as the game neared completion they had to set up the systems to sell the game. Jay Wilbur, who had been brought on as CEO and sole member of the business team, planned the marketing and distribution of "Doom". He felt that the mainstream press was uninterested in the game, and as id would make the most money off of copies they sold directly to customers—up to 85 percent of the planned US$40 price—he decided to leverage the shareware market as much as possible, buying only a single ad in any gaming magazine. Instead, he reached out directly to software retailers, offering them copies of the first "Doom" episode for free, allowing them to charge any price for it, in order to spur customer interest in buying the full game directly from id.
Official versions of Doom
"Doom" is one of the most widely ported first-person shooter video games. Starting with the original MS-DOS PC version (released as shareware on December 10, 1993), it has been released officially for a number of operating systems, video game consoles, handheld game consoles, and other devices. Some of the ports are replications of the MS-DOS version, while others differ considerably, including modifications to the level designs and monsters, with some ports offering content not included in the original MS-DOS version.