The CDF Primer is designed for scientists, researchers, programmers, and managers who want to learn about CDF without reading through this entire document or the programming reference guides. The primer will address what CDF is and how it can be used for storing and managing different types of data. A brief description of the tools and utilities available with CDF, in addition to program and toolkit examples, will be given. More detailed descriptions of the concepts presented herein are provided in the accompanying chapters of this document and the programming reference guides.