A "grammar check" is a tool or feature that helps users identify and correct grammatical errors in their writing. It analyzes text for issues such as sentence structure, punctuation, and word usage, ensuring that the writing is clear and coherent. Many word processing programs and online platforms, like Microsoft Word and Grammarly, offer grammar check functionalities. These tools can be particularly useful for students, professionals, and anyone looking to improve their writing skills. By highlighting mistakes and suggesting corrections, grammar checks help users learn from their errors and enhance their overall communication abilities.