Parappa the rapper is a ps1 game released in 1996 (if you were in japan, that is. If you were american you had to wait until 1997.) created by Masaya Matsuura with character designs & names coming from Rodney Alan Greenblat, and is commonly cited as the first rythim game, or "music video game" as it says on the back of the box.
it was, as you may know, wildly loved, becoming the 7th highest selling video game of 1997, along with Parappa (the character) winning the "best mascot" award at the 1997 editors choice of the inaugural Interactive Achievement Awards, beating crash bandicoot and lara croft.
Im not gonna explain the story or gameplay mechanics of PTR, if you're here id assume you already know that, and if you dont, watch like a playthrough or something idk