Ah, yes. Punctuation. The Golden Rule. Also the rule that so many like to spit on.

As we all know, punctuation exists to make sentences readable and understandable. It turns a bundle of words into coherent paragraphs and turns 'let's eat Grandma!' into 'let's eat, Grandma!' 

Without proper punctuation, your story will be very difficult to read. I find that examples work better than explanations, so here's a bit of work without any attempt at proper punctuation.  Ya know what? To make it extra cancerous, I'm gunna make it a Minecraft fanfic. HERE WE GO

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ScopeMaster_48 mined the cobblestone away breaking through to a huge cave  Behind, him PolarIceCaps9 pulled a fish from his inventory and started to devour. the items cubes flying every which way;

Scope shook, his head at Polars messy nature placing, torches to Light their way. Pick axe, scraping dully against the ground he moved forward eyes narrowed  the rattle of bones, echoed through the cave: a hiss sounding close behind it,

'Dang it$" Polar thought I;d just gotten healed too?"

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I'm not going to make you suffer through any more of that. But do you understand? Obviously, this was an exaggeration. Not many stories that I've seen are this bad, thank God, but some have come close. Misplaced commas, missing periods, incorrect sentence enders, absent apostrophes and quotations. All of this is necessary!

And make sure your punctuation is correct. Just because punctuation is there that doesn't mean that it's right. Read over your work to make sure it makes sense before you publish.