Radar imaging is an imaging method obtained by processing radar signals reflected from an object and generating an image of that object. The purpose of this article is to introduce basic concepts of radar imaging, including radar imaging geometry, synthetic aperture, stripmap mode, spotlight mode, and inverse mode. This article summarizes algorithms for radar imaging, including the range–Doppler algorithm, range migration algorithm, chirp‐scale algorithm, polar formatting algorithm, phase gradient algorithm, prominent point processing algorithm, and time–frequency‐based image formation algorithm. Issues in radar imaging of moving targets are also introduced.