IPS / UPS patch
Also known as: ips , ups , rom patch , rom hack patch
IPS and UPS are two binary patch formats used to ship ROM modifications without distributing the modified ROM itself. A patch file lists "at offset X, change bytes A B C to D E F"; you apply it to a clean original ROM and out comes the modified version. This is the standard distribution mechanism for fan-translations, romhacks, and bug-fix patches because the original copyrighted bytes never leave your disk. UPS is the modern format (handles ROMs of different sizes safely); IPS is the older one but still ubiquitous.