Wii homebrew

Homebrew is a term frequently applied to video games or other software produced by consumers to target proprietary hardware platforms (usually with hardware restrictions) not typically user-programmable or that use proprietary storage methods. This can include games developed with official development kits, such as Net Yaroze, Linux for PlayStation 2 or Microsoft XNA.

Many homebrew games are offered as freeware, although others are offered for sale, and some can be quite costly. One popular type of homebrew game is the fangame. In Japan, these games are usually called "Dōjin soft".

Homebrew games for older systems are typically developed using emulators for convenience, since testing them requires no extra hardware on the part of the programmer. Development for newer systems typically involves actual hardware given the lack of accurate emulators. Efforts have been made to use actual console hardware for many older systems, though. Atari 2600 homebrew developers use various methods, for example, burning an EEPROM to plug into a custom cartridge board or audio transfer via the Starpath Supercharger. Game Boy Advance homebrew developers have several ways to use GBA flash cartridges in this regard.

Along with the Dreamcast, Game Boy Advance, and PlayStation Portable, the most frequently used platforms for homebrew development are older generations of consoles, among them the Atari 2600 and Nintendo Entertainment System (NES). The Atari 2600 and NES use the 6502 instruction set, likely familiar to people who have programmed 8-bit home computers, such as the Commodore 64 or Apple II. Another factor in the popularity of older or portable systems for homebrew development, relative to modern consoles, is that their simplicity enables an individual or small group to develop acceptable games in a reasonable time frame.

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Wikipedia