Gens is an emulator for the Sega Genesis. It runs on Windows systems, using DirectX, and on Linux, using Simple DirectMedia Layer. The earliest (non-functional) release dates from 1999. As of September 2004, the current version (2.11) advertises full compatibility with "92%" of all Genesis games. As with all emulators, games (or ROMs) are not included and have to be downloaded separately.
Gens also supports running the Sega CD and Sega 32X, with plug-ins for the respective BIOSs, which are downloaded separately.
Another feature is support for the Kaillera Client, which allows games on the Gens emulator (as well as other emulators) to be played over a LAN or the Internet. However, on Gens at least, this is not as smooth a process as one would hope; a common problem is that on either PC, the other player appears to be a few seconds behind, this may result in them appearing to attack non-existant enemies for example.
Gens can also record what buttons are pressed and slow the gameplay down so it is used in making of tool-assisted speedruns.
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