What is a Lunar IPS patch?

A Lunar IPS patch modifies a read-only memory file, or ROM, typically used when emulating older video game consoles on a computer. Using the Lunar IPS program, one can create or apply the patch to a ROM file.

"Patch" in this case refers to a computing term meaning an update, fix or other modification applied to a file. Users create patches with Lunar IPS that, when applied to certain ROM files, change the game contained in the file. Video game ROM files are played using an emulator, a computer program that acts as a video game console. Using certain emulators, ROMs, or patches, may be illegal if the work is copyrighted and the user does not own the license or have permission.