Punctuation is an important part of written communication. Yet, over time the general population seems to have forgotten how to use punctuation properly or has simply stopped using it all together. There are many rules on using punctuation, and when not to. Commas, which are intended to separate clauses within a sentence, are not used at all on most signs, in social media, and even in written communication.
There is other punctuation that is commonly misused or left out; such as semicolons, question marks, periods, colons, and apostrophes seem to give many people trouble when attempting to incorporate into text. Although punctuation can be a little confusing sometimes, it's worth the effort to research and practice to write perfect sentences. But even the best writers (points finger to herself) can forget a comma here or a period there.
Since it's probably been a few (cough, cough) years since you thought about proper punctuation or looked at the rules, I have included a few links to help you polish up.
You're welcome :)