This chapter provides an introduction to Standard Commands for Programming Instruments (SCPI). The SCPI standard defines a set of programming commands and standards for use by all SCPI compatible instruments. SCPI is intended to provide a consistent environment for program development. It does so by defining standardized controller messages, instrument responses, and message formats for all SCPI compatible instruments. The following sections include descriptions of the command types, hierarchical command structure, command subsystems, data parameters, and notational conventions with examples.