Microsoft commissioned ambient musician Brian Eno to compose the startup sound for Windows 95, released in 1995, and the short melody became one of the most recognisable sounds in personal computing. As millions of people heard it every time they switched on their PC, it became shorthand for the mid-1990s home computer era. Decades later it survives in nostalgia videos, memes and retro tech content, where a few notes instantly transport viewers back to dial-up, chunky monitors and the first mainstream version of Windows.