what is a grammar
And why grammar is your friend... grammar (noun): the structure and system of a language, or of languages in general, usually considered to consist of syntax and morphology. Grammar is the system of a language. People sometimes describe grammar as the rules of a language; but in fact no language has rules*. If we use the word rules, we suggest that somebody created the rules first and then spoke the language, like a new game. But languages did not start like that.
Definition of grammar. 1  1a : the study of the classes of words, their inflections (see inflection 3), and their functions and relations in the sentenceb : a study of what is to be preferred and what avoided in inflection (see inflection 3) and syntax (see syntax 1)