This course examines mechanically addressed information storage devices, principally hard disk drives, but also magnetic tape systems, probe storage systems and optical disks. For all of these systems, the physics of the recording processes (magnetic, thermo-optical, thermo-mechanical,etc.) are examined in terms of design equations and noise sources. In parallel, an examination is made of a data storage channel and how data detection is accomplished in the presence of noise and the consequences of noise for error rate. A hard disk drive channel with Viterbi sequence detection and partial response equalization is used as the extended canonical example. After completing the course,students should understand how to estimate signal to noise ratio from an understanding of recording physics and use that to estimate system parameters like capacity, data rate and latency. Simple algorithms for estimating power and cost will also be considered. This course is evenly divided between signals and system considerations and device physics.