Reddit is the best, out of all meme sites. With with many different communities to choose from. Giving you the opportunity to choose to view memes that range from dark humor, to the most wholesome of memes.
Tumblr is almost as good as Reddit but they have less veriety, and there is less original content. However, most of the memes are original and even the stolen ones are funny, which gives it the number 2 spot.
Youtube has no original memes, but it has compilations of the best memes in long videos. All someone has to do to browse memes on youtube, is look up memes, and they will have be able to find videos that are ten minutes, to videos that are an hour. The lack of original content is overruled by the sheere amount of funny memes on the website.
Its like Tumblr, but worse.
Its like Reddit but much worse.