Columns (コラムス) is a puzzle game first created in 1989 by Jay Geertsen of Hewlett-Packard on the HP/UX with X Window System, with ports to DOS, Macintosh. Windows, and the Atari ST. In 1990, Geertsen sold the rights to Sega, where it was ported to the System C arcade board. This version was successful enough to be ported to various Sega and non-Sega hardware (including being both a Game Gear launch title and pack-in) and launched a series of sequels, that, despite bottomed-out popularity, continues to receive attention today.
Each console version of Columns adds several game modes:
2-player Competitive play: The original arcade version does have two players on screen at once, but this is not a competitive mode as players can join and leave at will.
Flash Columns: the player must mine their way through a set number of lines to get to a flashing jewel at the bottom. The faster the player accomplishes this, the higher his rank.
Furthermore, each individual port has its own features:
Master System/Game Gear: In single-player mode, the jewels can be changed to fruit, squares, dice, or card suits.
Mega Drive: Two game modes were added, accessible from the Menu option on the title screen menu. These modes can be applied to either the Original Game or Flash Columns.
Time Trial: Either Original Game or Flash Columns may be time-limited to three minutes.
Doubles: Either Original Game or Flash Columns may have two players competing on the same well instead of different wells
PC Engine: "Stone" and "Freeze" competitive modes (TODO)
Super Famicom: Media Factory also produced a SNES port of Columns under that name in 1999, also released exclusively in Japan — this time through issues of the Japanese version of Nintendo Power. This version includes a competitive play option, a tutorial, alternate jewel shapes, and an option to have jewels drop faster than usual from the get-go.
Manuals
Mega Drive Version
US Manual(info) ("Columns_MDUSManual.cbr" does not exist)