The Party Hard meme consists of a 2-frame animated GIF with the words "PARTY HARD" shopped into it. The GIF is edited to flash these frames very quickly, as if they are trying to induce a seizure in the viewer.
This meme originated from the video to Andrew W. K.'s song 'Party Hard', where Mr. W. K. is headbanging to the music in front of the words PARTY HARD, while strobe lights flash making his movements look jerky. The earliest known GIF to use this meme consisted of a 2-frame scene from the anime Azumanga Daioh, where Chiyo Mihama, dressed in a penguin costume, is doing her stretches.
It was most likely inspired by an anime music video of the same title. Even though it is a multi-creator video, the one "responsible" for this particular part is Jesmaster of Something Awful forums. While this meme does occasionally appear on /b/, its main home has been the /gif/ board, as one of the most controversial memes on that board. When asked about it, users either reply with "needs more party hard" or "nothing needs more party hard".
This extreme variation of opinions was further exacerbated by night-long Flame Wars between tripcoders Sempai's Pleasurous Nutrients and DammitQ. To show their contempt, other users would edit party hard GIFs to show a picture of a Penis or Harlequin Fetus as shock material. Supporters of the meme would edit almost any GIF they could find into a party hard. It made a brief, glorious reappearance as a counter-flood during the "gay /gif/" flood.
Party Hard was the 24M GET, for which the poster was banned.