The rapid increase in the use of software in airborne systems and equipment used on aircraft and engines in the early 1980s resulted in a need for industry-accepted guidance for satisfying airworthiness requirements. DO-178, "Software Considerations in Airborne Systems and Equipment Certification", was written to satisfy this need. This document, now revised in the light of experience, provides the aviation community with guidance for determining, in a consistent manner and with an acceptable level of confidence, that the software aspects of airborne systems and equipment comply with airworthiness requirements. As software use increases, technology evolves, and experience is gained in the application of this document, this document will be reviewed and revised. Appendix A provides the background of this document.