This paper summarizes research done in the area of electronic system reliability and assesses the approaches used in the calculation of electronic system failure rates. A detailed literature survey is conducted to investigate the various available reliability prediction models.The paper starts with a definition of reliability, briefly discusses various regions of system failure rate in time, justifies the role of reliability prediction methods, provides a historical overview, classifies the traditional models into easy to understand categories and discusses the advantages and disadvantage, reviews the key models that are currently in use, and compares the first and most widely used model (i.e., MIL-HDBK-217) with the most recently introduced model (i.e., PRISM).Index Terms-Electronic component reliability, empiricalbased models, failure rate, MIL-HDBK-217, physics-of-failure, prediction models.