This courselet provides a hands-on introduction to full disk encryption using the Linux dm-crypt subsystem and the cryptsetup tool. Learners will explore key concepts including the device mapper, dm-crypt, and LUKS (Linux Unified Key Setup), and gain practical experience encrypting block devices, creating secure mappings, and managing encrypted volumes. The courselet demonstrates the difference between encrypted and unencrypted devices by comparing raw disk content, and covers essential practices such as key management, mounting, unmounting, and secure cleanup. By the end, learners will be equipped to confidently implement and manage disk encryption in Linux systems.