The document discusses open-source and proprietary library catalog software. It defines open-source software and lists criteria it must meet including being freely redistributable and allowing modifications. Examples of open-source catalog software are provided like Koha and Evergreen. Factors to consider when choosing open-source software are also outlined. Proprietary software is created by vendors and available through paid licenses, which cover support and maintenance. Popular proprietary catalog systems like Voyager, Millennium, and SirsiDynix are mentioned. The document concludes that cost is important but not the only factor to consider, and that training, technical support needs, and ability to stay current also impact the choice between open and proprietary systems.