Word processing allows users to enter, edit, and format text and print documents. Key features of word processors include entering and editing text, formatting text alignment, styles, and page layout, and performing searches, spell checks, and grammar checks. Common methods for entering text are via keyboard, scanner, or optical character recognition software. Word processors also enable global and selective search and replace functions. Spell checkers compare words to a dictionary, while grammar checkers highlight potential errors. Standard letters and mail merge allow inserting variable details into pre-made templates.