CIP RC/PT Girder groups commonly used data together in the form of libraries. Libraries are used to store data not susceptible to change and able to be used in projects repeatedly. CIP RC/PT Girder has a set of default libraries for mild steel reinforcement, vehicles, and post-tensioning tendons. The individual libraries are stored as files, each containing different items. For example, two separate rebar library files named "MetricRebar.rlb" and "EnglishRebar.rlb" may contain standard rebar defined for metric use and English use respectively. Many users may find it convenient to work with a single library file, modifying, adding, and deleting items in these files rather than creating and setting up different and/or multiple library files.