Multi-track recording (8 track) became common in which decade?

Multi-track recording (2-4 track) became common in which decade?

Digital recording using magnetic tape (ADAT/ DASH) was mostly used in which decades?

Digital recording using hard disc systems was most common in which decade?

Digital recording using Digital Audio Workstations (DAW) became common in which era?

Analogue synthesisers would be most common in which eras?

Digital synthesisers would be most common in which era?

Sampling parts of other people's tracks became common in which era?

Digital Sampling libraries for use in DAW's became most common in which era?