For most of us, we don't know what it means. In a nutshell, Article 13 bans memes, and most copyrighted stuff. So that memes that next time post a meme in the EU, you are illegally doing it. To get a full explanation, watch this video.
Now, how does affect you, my US viewers? Well, all of your favorite YouTube creators who HAPPEN to be living in the EU (lets say IHE), there practically blocked from posting, and you wont be able to get videos from them. This is bad for us, but to top it all off, other media companies in the US or in any country in that matter will start petitioning to bring these regulations to there native soil, which means that yes, one day, we may have Article 13: US edition.
How can you stop this you are asking (I hope). Well... Upvote this dispatch, share websites that are opposed to it, and spread the word.