“What’s Up?” was written by Linda Perry alone in a small room. She was frustrated with her life and the music industry, and the lyrics came out in about thirty minutes of improvisation, including the now-famous “What’s going on?” The band’s label, Interscope, recognised it as a potential hit, but Perry hated the original production and re-recorded the song with the group in a single day. Released in 1993 as a single from Bigger, Better, Faster, More!, it became 4 Non Blondes’ only major hit, reaching No. 14 on the Billboard Hot 100, No. 2 in the UK and No. 1 in more than ten countries. Perry later became a highly successful songwriter and producer, writing “Get the Party Started” for Pink and “Beautiful” for Christina Aguilera, among many others.

“Toxicity” is the title track from System of a Down’s 2001 album Toxicity. The politically charged song reached No. 25 on the UK Singles Chart, No. 10 on the US Mainstream Rock chart and No. 3 on the US Alternative Airplay chart, becoming one of the band’s biggest hits. The album was released just one week before 9/11. In the aftermath, some radio stations temporarily pulled System of a Down material, most notably the earlier single “Chop Suey!” because of lyrics that felt newly sensitive after the attacks, even though those words had been written long before the events.