In an interview with the New Musical Express December 8, 2007, vocalist Thom Yorke was asked if songs like "All I Need" are about obsession. He replied: "That's why it's called 'In Rainbows.' That obsession thing, thinking beyond where you are at the time. It's a phrase I had for a while, it kept coming up in my notebooks. And I don't know why, because it's kind of naff. But it seemed to work-it's one of those weird things. It stuck and I don't know why."
The lyric "I'm (just) an insect" is a direct quote from New Wave UK band Magazine's 1980 track "A Song From Under The Floorboards." Magazine front man Howard Devoto's existentialist lyrics were an early influence on Thom Yorke.
In the same New Musical Express interview, Thom Yorke spoke about the complexity of recording the songs on the album. He said: "We deliberately did this thing to get a series of disembodiment when we were assembling tracks. So the vocal may be from one version or the drums may be from another. If there was something that you were particularly fond of you kept it from that take and forced it on the other version. For instance 'All I Need' was the outcome of four different versions of it. It was all the best bits together."
In an article in the New York Times December 9, 2007, Jonny Greenwood said that for this song, he wanted to recapture the white noise generated by a band playing loudly in a room, when "all this chaos kicks up." In an artificial studio setting he found it impossible to generate such a sound so his solution was to use a string section, and his own overdubbed violas, sustaining every note of the scale, blanketing the frequencies.
The MTV Exit (end exploitation and trafficking) campaign and Radiohead jointly produced a video for this track in order that such issues as child slavery, enforced servitude and sex trafficking be highlighted. Thom Yorke told The Hollywood Reporter via Billboard.com, that it was "about exploiting a situation while you have the chance. All power to MTV for taking this on because its obviously going to be difficult for them in terms of the advertisers. If you talk about slave labor, then the issue of cheap goods from the East is all about that. With the [video their lawyers had to beg to make sure there wasn't a single white [sneaker] with a logo on it because the implication would be a little too close. But the implication is still there. If [MTV] are able to break the taboo of enslavement and put it onto the agenda then its a good thing. If they get people to think in terms of the profits we make in the West because of cheap labor, then that's a good thing."