Over the 19 years since the VLBA dedication in 1993, many individuals have contributed to this document by writing sections, editing previous versions, commenting on draft material, and implementing the capabilities described herein. We thank all these contributors for their efforts. The editor of the present version of this document is responsible for the most recent revisions, and thus is the best contact for readers who may have questions on the material, or suggestions that would enhance the usefulness of this guide.