Grammar, usage and mechanics refer to the use of proper syntax, punctuation, and writing conventions. They are the rules that govern the way a written language is expressed.
Grammar deals with the structure of language and includes parts of speech (e.g., nouns, verbs, adjectives, adverbs), punctuation, capitalization, gender, number and verb tense.
Usage refers to the accepted usage of words, phrases and conventions. Usage may vary between different regions and is often dictated by local customs.
Mechanics is the application of rules for writing, such as spelling, grammar, usage, punctuation and capitalization. The purpose of mechanics is to improve the readability of a document by ensuring that all words, ideas and concepts are expressed in a clear and consistent manner.
Grammar, usage and mechanics are vital for effective communication. A well-written document demonstrates a level of professionalism, is easier to read and understand, and conveys the intended meaning more accurately to the reader. Being aware of and adhering to proper grammar, usage and mechanics is essential for anyone who wants to write in a clear and concise manner.