A license or product key generator (keygen) is a computer program that generates a product licensing key, serial number

Serial number

A serial number is a unique number assigned for identification which varies from its successor or predecessor by a fixed discrete integer value...

, or some other registration information necessary to activate for use a software application.

Software licensing

A software license is a legal instrument that governs the usage and distribution of computer software. Often, such licenses are enforced by implementing in the software a product activation

Product activation

Product activation is a license validation procedure required by some proprietary computer software programs. In one form, product activation refers to a method invented by Ric Richardson and patented by Uniloc where a software application hashes hardware serial numbers and an ID number specific...

 or digital rights management

Digital rights management

Digital rights management is a class of access control technologies that are used by hardware manufacturers, publishers, copyright holders and individuals with the intent to limit the use of digital content and devices after sale. DRM is any technology that inhibits uses of digital content that...

 (DRM) mechanism seeking to prevent unauthorized use of the software by issuing a code sequence that must be entered into the application when prompted or stored in its configuration.

Availability

Keygens are available for download on various websites dedicated to bypassing of product registration and activation, or to software piracy in general. In most countries, the use of keygens to activate software without purchasing a license is fraudulent.

Keygen software distributions may be infected with malware

Malware

Malware, short for malicious software, consists of programming that is designed to disrupt or deny operation, gather information that leads to loss of privacy or exploitation, or gain unauthorized access to system resources, or that otherwise exhibits abusive behavior...

 by third parties.

See also

• Hacker (programmer subculture)
• License manager
  License manager
  A license manager is a software management tool used by software vendors or by end-user organizations to control where and how software products are able to run. License managers protect software vendors from losses due to software piracy and enable end-user organizations to enforce compliance with...
  
  
• Product activation
  Product activation
  Product activation is a license validation procedure required by some proprietary computer software programs. In one form, product activation refers to a method invented by Ric Richardson and patented by Uniloc where a software application hashes hardware serial numbers and an ID number specific...
  
  
• Disassembly