What does OPAC stand for in library terminology?

The term OPAC stands for Online Public Access Catalog. This definition is crucial in the context of library science, as OPAC refers to the online system where library users can search for and access bibliographic information about the materials available in the library's collection. The focus of OPAC is on public access, indicating that it is designed for use by patrons to help them discover resources, check availability, and sometimes even access electronic materials directly.

In the realm of library services, having an Online Public Access Catalog enhances user experience by allowing patrons to engage with library resources remotely and easily. This system can include various features like search functionalities, the ability to reserve materials, and information about circulation status.

The other options, while they may sound similar, do not accurately represent the term used in library settings. For example, "Open Public Access Catalog" would imply a different meaning, not specifically indicating that it is an online system. The phrase "Online Private Access Catalog" suggests limited access, which is not in line with the public aspect that OPAC embodies. Lastly, "Open Private Access Catalog" further diverges from established terminology in library science. The clarity and specificity of the correct answer emphasize the importance of accurate definitions in the field.