- This is about the money-grubbing record producers and managers controlling the band, which contributed to Pink Floyd founder Syd Barrett's mental collapse. The world around him was like a machine: the fans, the group, the record industry. They told him what to do and when to do it so they would become successful. The Wish You Were Here album this song is on revolves around Syd Barrett and what contributed to his collapse.
- This song features a very rare music video only played during concerts. It features a particularly visceral depiction featuring corpses, rats, death, and waves of blood. The video was drawn by hand by Floyd's old friend, Gerald Scarfe.
- Both the music and the lyrics were written by bassist Roger Waters.
- The track was built upon a basic throbbing sound made by an EMS VCS 3 followed by a one-repeat echo which Waters would have played originally on bass guitar (which he overdubs an actual bass part to the song which is more predominant on the Stereo Quad mix).
- David Gilmour admitted that he had trouble singing one line of the song, saying, "It was a line I just couldn't reach, so we dropped the tape down half a semitone." He sang the part at a slightly lower pitch, then the tape speed was raised back to normal.
- Like many Pink Floyd songs, "Welcome to the Machine" features some variations in its meter and time signatures. Each bass "throb" of the VCS synthesizer is notated as a quarter note in the sheet music, and each note switches from one side of the stereo spread to the next (this effect is particularly prominent when listened to on headphones). Although the introduction of the song (when the acoustic guitar enters) does not actually change time signatures, it does sustain each chord for three measures, rather than two or four, resulting in a nine-bar intro where an even number of bars might be expected. The verses and choruses are largely in 4/4, or "common time". However, on the line "It's all right, we know where you've been", a measure of 7/4 is inserted, shortening the sequence, and causing the left-right stereo panning to be reversed for quite some time. An instrumental section begins, with the acoustic guitar adding variations in its strum pattern, until it switches to 3/4 for a length of time, when a 12-string acoustic riff is introduced, ascending up the E minor scale until the chord changes to C major seventh. Finally, the instrumental section ends, and the second verse begins. With the lyric, "It's all right, we told you what to dream", once again a measure of 7/4 is inserted, and the stereo panning is finally returned to normal. Incidentally, these two phrases beginning with "It's all right ..." are the only parts to feature any chord other than some form of E minor or C major—these phrases go to an A bass in the first verse, and in the second verse, the acoustic guitar articulates the A as a major chord, with its C# in contradiction of the frequent C chords. The song remains in 4/4 from this point forward.
- The live renditions of the song were complex because music had to be synchronised with the backdrop film and its sound effects. As a result, the band had to wear headphones and listen to a click-track which, in turn, meant that there was very little room left for improvisation.
Thanks for reading!