is a Japanese visual novel

Visual novel

A is an interactive fiction game featuring mostly static graphics, usually with anime-style art, or occasionally live-action stills or video footage...

 developed by Key

Key (company)

Key is a Japanese visual novel studio which formed on July 21, 1998 as a brand under the publisher Visual Art's and is located in Kita, Osaka, Japan. Key released their debut visual novel Kanon in June 1999, which combined an elaborate storyline, an up-to-date anime-style drawing style, and a...

 and originally released as an adult game

Eroge

An or Ero-ga is a Japanese video or computer game that features erotic content, usually in the form of anime-style artwork. Eroge originated from galge, but unlike galge, they feature erotic/pornographic content.-History:...

 on June 4, 1999, playable on a Microsoft Windows

Microsoft Windows

Microsoft Windows is a series of operating systems produced by Microsoft.Microsoft introduced an operating environment named Windows on November 20, 1985 as an add-on to MS-DOS in response to the growing interest in graphical user interfaces . Microsoft Windows came to dominate the world's personal...

 PC

Personal computer

A personal computer is any general-purpose computer whose size, capabilities, and original sales price make it useful for individuals, and which is intended to be operated directly by an end-user with no intervening computer operator...

. An all ages version for the PC was released in January 2000, and was later ported to the Dreamcast, PlayStation 2

PlayStation 2

The PlayStation 2 is a sixth-generation video game console manufactured by Sony as part of the PlayStation series. Its development was announced in March 1999 and it was first released on March 4, 2000, in Japan...

, and PlayStation Portable

PlayStation Portable

The is a handheld game console manufactured and marketed by Sony Corporation Development of the console was announced during E3 2003, and it was unveiled on , 2004, at a Sony press conference before E3 2004...

. The Kanon Standard Edition was released for the PC as an adult version in November 2004 and an all ages version in January 2005. Both Standard Editions are playable as a DVD-ROM and incorporate the extra graphics added to the earlier all ages version of the game, added support for Windows 2000

Windows 2000

Windows 2000 is a line of operating systems produced by Microsoft for use on personal computers, business desktops, laptops, and servers. Windows 2000 was released to manufacturing on 15 December 1999 and launched to retail on 17 February 2000. It is the successor to Windows NT 4.0, and is the...

/XP

Windows XP

Windows XP is an operating system produced by Microsoft for use on personal computers, including home and business desktops, laptops and media centers. First released to computer manufacturers on August 24, 2001, it is the second most popular version of Windows, based on installed user base...

, and other technical changes such as more save slots.