This is a track from American rapper Jay-Z's eighth LP, The Black Album. The song was produced by Just Blaze and samples "Seed of Love" by Little Boy Blues.
Both Clipse's "Number One Supplier" and Beanie Sigel's "All the Above" borrow lines from this song.
Jay-Z wrote the second verse of this track after a journalist went over the top in interpreting the symbolism in one of Hova's outfits. He recalled to MTV News: "The second verse of 'PSA' may not have that many hidden jewels in [it], but the story behind why I wrote the second verse is pretty interesting. It's sort of that look on rap, how this writer had written this article about me wearing this Che Guevara shirt [with a] Jesus piece, and she was like, 'The Jesus piece is hitting his head,' and I was like, 'You're going a little too far. It's a T-shirt and a chain. It's not literally hitting his forehead. That [experience] inspired the entire verse. 'I'm like Che Guevara with bling on, I'm complex.'"