What is a meme coin?

Could you elaborate on the concept of a "meme coin" in the cryptocurrency landscape? I've heard the term mentioned frequently but am still unclear on its precise definition and significance. Is it simply a coin that gains popularity through internet memes or does it possess some unique financial attributes? Additionally, how do meme coins differ from traditional cryptocurrencies in terms of their value proposition and investment strategies? Your insights would be greatly appreciated in demystifying this growing phenomenon.