There are two types of people who talk about grammar on the internet: those who pedantically criticize every real and imagined misuse, and those who rant on Tumblr that they’re gonna write however they want cuz that first type can suck it. Both types have entirely missed the point of grammar.

Grammar functions as a tool to make your writing readable. That’s it.

It’s not a list of rules that have to be followed at all costs. It’s not a bunch of arbitrary legislation designed to give you a hard time. It’s also not an optional guideline that you can follow if you want to. Nor is it something that an editor will fix for you later. It is an intrinsic part of language, and it exists to help you be a better writer. If no one ever explained this to you, I apologize on behalf of writers and educators everywhere.

The misconceptions tend to start early, when a classroom of students is handed a worksheet and expected to memorize it for the test. Commas belong in lists. Periods come at the ends of sentences. Apostrophes make contractions. Don’t split infinitives. Don’t end a sentence with a preposition. Don’t write run-ons or fragments. A couple is two, a few is three, many is four or more. The list is endless, because there’s a lot of nuance to language.

These “rules” are annoying to memorize and nearly impossible to retain, so those that manage it become pedantic, and those who don’t become surly. Neither, however, understand grammar.

Think of it this way: grammar is to writing what a score or soundtrack and sound effects are to a movie. It’s not directly noticeable, but it cues the consumer to experience the piece in a certain way. It emphasizes certain parts and downplays others. It guides you from beginning to end, keeping you from being confused, allowing you to lose yourself in the piece and not think about the fact that you’re reading a book or watching a movie. Now, a movie can be made without music and sound effects, much as a book can be written without proper grammar, but unless you’re really talented and really intentional, that movie and that book are going to be downright terrible.

Humans are wired to recognize patterns. And then, once those patterns are internalized, we forget they’re there. Don’t cross this street without looking both ways becomes don’t cross any street without looking both ways. Which then becomes the much simpler, don’t get hit by a car, which, of course, is achieved by looking both ways before you cross. In a movie, we’ve been trained to recognize that minor keys mean sad scenes and increasing tempos cue action or suspense. As written language evolved, grammar developed so that a sentence could be understood the same way one person to the next to the next to the next. Exclamation points are used to express exclamations, always. When you stray from these conventions, readers are left to puzzle out what you mean on their own, often coming to the wrong conclusions.

Everyone has seen this example:

Let’s eat Grandpa!
Let’s eat, Grandpa!

The comma changes the meaning of the sentence. Cannibalism becomes a call to dinner. This is what we’ll refer to as necessary grammar. Necessary grammar is the purely functional rules that render your writing sensical. Commas in lists. Possessive apostrophes. Subject-verb agreement. Etc. No matter how unique you want to be, you can’t ditch this kind of grammar. If you do, your words not only won’t mean what you want them to mean, they probably won’t even make sense. These are the rules you have to memorize, because that’s just how our language evolved.

But take another example:

Keep walking, Bob. Will, go around back. To work! Now!
Keep walking—Bob will go around. Back to work, now.

Here we have the same words in each sentence, but, thanks to grammar and punctuation, two very different scenes. In the first, we have someone giving orders to Bob and Will, possibly for a heist, or something time sensitive. In the second, someone is much more calmly giving instructions to an unnamed person before reminding them to get back to work.

Changing the punctuation or a word’s assigned part of speech can change the meaning of the sentence. We’ll call this creative grammar. Creative grammar is very similar to necessary grammar, in that you need to memorize the functions of each grammatical element before you mix and match it, but it can be mixed and matched. Switching up sentence structure, using em dashes or ellipses—these are all creative choices, meant to achieve an effect.

Since a reader has been conditioned to read a certain way—just as a movie viewer is conditioned to recognize that certain sounds mean certain things—a writer’s job is to work within the reader’s expectations until a certain sentence or scene requires you to upset those expectations for effect. A slow-motion montage with melancholy music is expected to be a sad scene. When it’s juxtaposed with happy images, expectations are upset, and a humorous effect is achieved.

Writing a long, winding sentence with no punctuation whatsoever is not grammatically correct. If you write your entire book like that because you never took the time to learn grammar, no one, especially not an editor, will read it. But if your entire book is grammatically correct up until a scene where a character is having a mental breakdown, and then you write a long, winding sentence with no punctuation, you’ve achieved a powerful effect on the reader, giving a glimpse into that character’s mind. The same goes for sentence structure. If you write a book with mixed up subjects, verbs, and agreements, you’ve written a bad book. But if you write the dialogue of an English-learner with mixed up structure and agreement while the rest of your book is grammatically correct, you’ve made the characters that much more real.

On the flip side, writing an English-learner with consistently proper grammar—because you know the rules of grammar goshdarnit—isn’t going to do your book any favors.

Also, correcting people’s grammar is annoying. The urge is understandable, but unless the other person is legitimately going to learn something and appreciate your correction, it’s not worth it. Being pedantic about grammar just makes people hate it all the more. Grammar isn’t a list of rules that you need to enforce, it’s a tool for understanding.

A good rule of thumb for your writing is to ask yourself, is there any way to misunderstand this? If the answer is yes, rewrite it with better grammar.

Know the rules before you break them.

Look up grammar rules you don’t understand. Make sure you’re consistently using commas correctly. Learn how to diagram sentences. And once you know the rules of grammar—really, confidently know them—you’re allowed to break them. Shakespeare just up and made up words. But he did so understanding their functionality and parts of speech. The main goal is to make your writing readable and enjoyable, and to make sure you’re communicating exactly what you want to say. If you put in the work to learn and understand, grammar will help you with that, rather than hinder you.