ROM emulation is the process of copying data from a ROM (read-only memory) chip to a storage medium such as a hard disk or flash memory. ROM emulation is especially popular among gaming enthusiasts. With the help of a software program called a ROM emulator, an old game can be made to run on a new computer when it won't play directly.
Some people use ROM emulation to modify existing games for personal purposes. For example, the difficulty level can be changed, the graphics can be altered, or the native language can be translated so that users from another country can play the game. However, ROM emulation is commonly carried out to make free copies of games. In some countries, this activity is legal, but in others, including the United States, it is not.
In an attempt to combat computer-game piracy, some vendors have incorporated anti-copying codes into their game files. However, skilled and determined hackers can circumvent these codes. In recent years, the gaming industry has claimed significant revenue losses as a result of this form of piracy, which they regard as copyright infringement.