Giphy: This is a good GIF because it's so triumphant, but its straight-up weirdness elevates it to a great GIF. Plus, this is the perfect GIF to use for a self-congratulatory Tweet (so, basically, every Tweet.)
Giphy: I see this GIF being used a lot, under many contexts. It can be sweetly romantic, or a way to say "thank you," or just a funny animal GIF. That's one of my favorite things about GIFs—a simple, eight-frame animation of a walrus can mean so many things!
Giphy: There are all different "volumes" of laughing GIFs, from a polite chuckle to, well, this GIF. Brendan Fraser's laughter is so unhinged, it's almost cartoonish, and the looping amplifies it perfectly. If you're going to go big, this is the GIF for you.
Three-way tie between Arrested Development, The Office, and Tracy Morgan in Cop Out
Giphy: This was the hardest reaction to decide on a single best GIF. In all honestly, the "No" Reaction GIF has a holy trinity. Michael Bluth, Michael Scott, and Tracy Morgan. They're all playing off the same concept (an extendedly pointed "no"), but they're so funny and so full of emotion that they've yet to become stale.