50 Years of Proof Assistants
This article traces the 50-year history of proof assistants—software tools that help mathematicians and computer scientists construct and verify formal proofs. It covers key milestones from early systems like AUTOMATH in the 1960s through modern tools such as Isabelle, Coq, and Lean, highlighting how these systems evolved from niche research projects into powerful platforms now used in verifying software, hardware, and mathematical theorems.