The 'Oh yeah! Oh no...' meme format typically features a character experiencing a moment of pure excitement followed by a sudden, often devastating, realization. While the phrase is famously associated with the Kool-Aid Man’s signature catchphrase, the meme format gained significant traction through various webcomics and animated parodies like Family Guy. It is used to illustrate scenarios where a situation seems positive at first glance but reveals a hidden downside. Today, it remains a staple for internet users to mock their own poor decisions or the irony of life's unexpected twists.