Cracks are programs created to remove the restrictions of the software for avoiding the payment that is asked in exchange for the licensed version. Usually, this is done by modifying the software or generating its registration code with the help of specific software. When active, cracks are capable of adding (or removing) needed registry values, files (.dlls, executables, etc.) and similar components. In addition, they can change specific parts of software by altering its code and initiate other alterations. Finally, they can try to guess or generate the registration code and use it for the registration of commercial software. Each of these changes can remove the restrictions of the program. Such software is considered 'cracked'. In most of the world's countries, the use of cracks and cracked software is considered illegal.