Optical lithography provides a high-productivity, profitable means of making microcircuits on silicon wafers by imaging increasingly smaller features in photoresist. Polarization lithography specifically refers to the use of polarized light for illumination within an optical lithographic system to improve the quality of the imaging and the resolution. In the quest for ever-greater resolution, modern fabrication facilities all use some form of polarization lithography to produce high-technology computer chips. This article discusses basics of polarization lithography and why it is important.