This is very simple rock song, but its melody and syncopation help to make this an addictive song.
Most of the effectiveness of this song is because of the rhythm of the guitar. Rather than staying on the beat like many rock songs do, the rhythmic line of the introduction and verses is 1 (2) & (3) & (4) e. This gives the song a very fun and driving feeling. This rhythmic line is strengthened by the vocal part in the introduction (short phrase of several "whoa's" that happens between each chorus and verse) and the verses doing the same rhythm (except for the & of 2). The drum part forms the stability of the verse with the hi-hat doing usual eighth notes and snare drum on 2 and 4 but during the introduction the drums has sixteenth note tom solos during the second half of each measure which adds to the instability.
The chorus represents a stability in the guitar part that lacks any syncopation, but the snare drum part strays from the usual 2 and 4 by doing some offbeats of 2 and 4 which reflect the emphasized parts of the vocal line during the chorus. The change of the part that makes the song unstable is a very effective way of getting the listener to pay attention to different things.
After three intros, two verses and two choruses, the guitar solo begins. The overall feel of the guitar solo is the same as one of the verses, but the syncopated background is less apparent because is just the bass and drums doing this while the guitar is doing its own solo which does many sixteenth note runs while spending some time emphasizing the rhythm.
The chorus goes through one more time, followed by the introduction again, which gets extended by a measure where the background music switches to just eighth notes and does a slight ritardando to show that the song is ending, because previously the intro has always lead directly into other material.
This is a really fun song that has an effective rhythmic structure to give the song a somewhat unsteady but funky feel.