Open-source software is software that has its source code available for anyone to inspect, modify, and distribute. Open-source software is usually free of charge and does not require a license to use. Some examples of open-source antivirus software are ClamAV, Comodo, and Immunet12. The other license types are either not free or not suitable for a SOHO PC. Corporate and enterprise licenses are designed for large-scale organizations and networks, and they usually require a subscription fee. Personal licenses are for individual users and may have limited features or support.