Radar imaging is a technology that has been developed, very successfully, within the engineering community during the last 50 years. Radar systems on satellites now make beautiful images of regions of our earth and of other planets. One of the key components of this impressive technology is mathematics, and many of the open problems are mathematical ones. This presentation will explain, from first principles, the basics of radar and the mathematics involved in producing high-resolution radar images. This theory will also be helpful to those interested in other areas involving wave propagation, such as seismology, underwater acoustics, and medical ultrasound imaging.