A common complaint about bands like AC/DC is that they've been writing and recording the same album for twenty years. A further criticism is that all of their songs are the same. This is not quite true. I cataloged the various AC/DC songs in 2008. Following a long-standing argument between me and Eric regarding the true number of AC/DC songs (six or four), I present the following analysis of the six songs of AC/DC. This analysis is on the music, not the lyrics, which would be the subject of a different post.

1. The song with the stop-start riff. This is a staple of the AC/DC canon. This song is based on a mid-tempo riff with a double-stop or a riff featuring one or two long rests. The song can start with the riff played by itself as an intro(1), with a separate intro(2) or full band start(3).
   examples:
   • Highway to Hell(1)
   • Back in Black(3)
   • TNT(2)
   • Whole Lotta Rosie(1)
   • You Shook Me All Night Long(2)
2. The song with the big intro. This is a less common song, but generally used to good effect. Songs in this category are some of the best well-known of AC/DC's songs.
   examples:
   • Thunderstruck
   • Riff Raff
   • Hell's Bells
3. The song with the fast riff. This one is built around a quick riff with a fast run of single notes, rather than a serious of chords.
   examples:
   • Heatseeker
   • Riff Raff
   • Beating Around the Bush
4. The four-on-the floor song. This song features a vocal melody that plays of a riff built around a four-on-the-floor drum pattern (kick drum on all the downbeats). This is another AC/DC staple. If you think about it, Rock 'N' Roll Singer is really just a rewrite of It's a Long Way to the Top without the bagpipe solo.
   examples:
   • It's a Long Way to the Top (If You Wanna Rock 'N' Roll)
   • Sin City
   • Girls Got Rhythm
5. The slow, bluesy song. These show AC/DC's basis in the blues and in 50's rock and roll. They were more common in the Bon Scott era than later. A variant is a sped-up version of a blues/50's rock riff. The album version of Rocker is an example, although live it was played much slower.
   examples:
   • The Jack
   • Ride On
   • Rocker
6. The Big Riff. The strength of the Young brothers' songwriting is huge guitar riffs, ones that are often more memorable than the vocal melodies or the lyrics. This song is a staple of the AC/DC set and is based around a huge riff (and often lyrically is based around a chorus consisting of the song title).
   examples:
   • Rock 'N' Roll Damnation
   • If You Want Blood (You've Got It)
   • Dirty Deeds Done Dirt Cheap

Not every AC/DC song fits neatly into these categories. They do mix and match them at times. A good example is "Riff Raff" from the Powerage album, which combines the big intro with the fast riff. As an aside, this is, as far as I'm concerned, their best song and the album in general is seriously underrated.