“Undone – The Sweater Song” was Weezer’s first single off their self-titled 1994 debut album.

Frontman Rivers Cuomo has commented on the song to Rolling Stone:

“‘The Sweater Song’ was the first Weezer song I ever wrote, back in 1991,” Cuomo says. “I was trying to write a Velvet Underground-type song because I was super into them, and I came up with that guitar riff. I just picked up that acoustic guitar and the first thing I played was that riff. And it just feels so classic to me, even now when the band starts to play it, it just takes over the energy in the room and you’re just transported into the world of Weezer. It wasn’t until years after I wrote it that I realized it’s almost a complete rip-off of ‘Sanitarium’ by Metallica. It just perfectly encapsulates Weezer to me – you’re trying to be cool like Velvet Underground but your metal roots just pump through unconsciously.

Cuomo has also said {citation needed}:

“Undone” is the feeling you get when the train stops and the little guy comes knockin' on your door. It was supposed to be a sad song, but everyone thinks it’s hilarious.