This is the joint that when you hear it you like, "That’s my shit!"

from Logic – All I Do Lyrics on Rap Genius

Meaning

Everybody has at least one jam that when they hear it, as soon as that first note hits their ear, they think, “THAT’S MY JAM!”

Some would say it’s this song. But we all know that you’ve jammed hard to a different tune…
http://www.youtube.com/watch?v=Cv2g0yxjs5k

The joint is also a tie into the end of the next line about getting lit.

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