In the early 2000's, Homestar Runner was one of the most popular sites on the internet, and according the A.V. Club, it was "the first online provider of TV-like content to see significant crossover success."
The flash-animated cartoon series featured a group of outrageous characters, most notably Homestar Runner (shown above), an earnest and dorky athlete as the main character, and his snarky arch-nemesis Strong Bad, who was continuously donning a Lucha libre-style mask and boxing gloves. Over time, the site grew organically until a series entitled Strong Bad Email, in which Strong Bad answers fanmail from viewers, exploded and became the most popular destination on the site and the web.
For the next decade or so, creators Mike and Matt Chapman churned out cartoons, while refusing to succumb to advertisers, unofficially ending the series in 2010. However, after releasing a new cartoon on April Fool's Day, which Matt later indicated as a "sort of test," it is now clear that Homestar Runner is trying to make a comeback!
So to celebrate (and to catch everyone else up what this is), here are a few of the most popular features from Homestar Runner: