In order to reduce design-cycle time and physical prototyping, equipment manufacturers need to ascertain the thermal performance of new systems at the earliest possible stage of the design process. In the early 1990s, some European industries began to realize that the accurate prediction of the temperatures of critical electronic parts at the package, board, and system levels was seriously hampered by a lack of reliable, standardized input data that characterize the thermal behavior of these parts. It was the start of a number of European projects concerned with the creation and experimental calibration of thermal models for a range of electronic parts. The ultimate goal of these projects was to get component manufacturers to supply calibrated compact thermal models (CTMs) of their parts to end users by adopting the experimental techniques used to calibrate the detailed thermal conduction models of the parts and the methods to generate compact models. This review paper is written with the purpose of presenting a condensed overview of the history, background, philosophy, methodology, and standardization aspects of compact thermal modeling to non-experts. Some space is devoted to the basic concepts of thermal resistance and thermal characterization because many designers have an incorrect perception of the physics underlying these concepts.