init. all-in-one (especially referring to computers, where all components exist as a single unit, rather than as separate pieces)
Äio is the release from Estonian folk-metal group Metsatöll. It was issued in 2010 on Spinefarm Records all over the world. It features heavy use of traditional instruments such as the lokulaud, torupill, kannel & angipill, in addition to the typical metal band instrumentation (electric guitars, bass, drums, etc.)
Aio (supposedly died 974) was a fabricated English monk of Crowland Abbey in Lincolnshire and historian. The Oxford Dictionary of National Biography strongly suggests he never existed.