Rhett and Link met in the first grade, and have been best friends for 30+ years.
A recurring element of the show is that whenever the word "Tokyo" is mentioned, Rhett must say "whhhaaaattttttt". This stems from the episode "Odd Self-Defense Techniques" at 8 minutes 10 seconds. Commenters have highlighted times Rhett failed to do this on several episodes, which led to him doing a "whhhaaaatttttt" that lasted for almost 1 minute in "Eel slap to the face".
A recurring joke in the show is whenever Rhett and Link do anything in a bath towards the end Link will find a can of Sprite which has been sitting in the bath.
Good Mythical Morning (GMM) started on January 9, 2012
Some of the most popular episodes of Good Mythical Morning are the "Will It?" episodes, in which odd combinations of food are taste-tested by Rhett and Link, such as replacing the ice cream in an ice cream sandwich or the filling in a taco with a strange ingredient. Sometimes they see if different objects can perform tasks they're not designed to do. As of December 2016, there have been 30 "Will It?" episodes released: Will It Taco, Ice Cream Sandwich, Double-Awesome, Deep Fry, Cereal, Pumpkin Spice, Jack-o-Lantern, Popsicle, Donut, Valentine, Pizza, Shoe, Vacuum Seal, Hot Pocket, Cookie, Jello, Chocolate, Smoothie, Pie, Eggnog, Dumpling, Fondue, Pancake, Soup, Burger, Pickle, Sushi, Burrito, Candy, and Corndog.