The phaco chop technique was first described in 1993 by Kunihiro Nagahara, MD, at the American Society of Cataract and Refractive Surgery (ASCRS) Annual Meeting in Seattle, Washington, where his film Phaco Chop received an award. Phaco chop and its many variants subsequently revolutionized the approach to nucleus-fracture techniques in cataract surgery. This two-part article examines the basics of phaco chop techniques. In this first part, we summarize the principles of chopping, the types of chopping, and the technologies it entails. The second part will explore chopping techniques and how to pick the best approach based on case-by-case variables.