Proof assistants are software tools designed to help users construct and verify mathematical proofs. They provide a formal framework where users can express mathematical statements and reason about them using logical rules. By doing so, proof assistants ensure that the proofs are correct and free from errors, which is especially useful in complex areas of mathematics and computer science. These tools often use a programming language-like syntax, allowing users to write proofs in a structured manner. Popular proof assistants include Coq, Lean, and Isabelle, each offering unique features and capabilities. They are valuable in both academic research and practical applications, such as verifying software correctness.