During WWDC 2020, Apple officially (and finally) announced the transition of Mac hardware to their own developed chips. The ARM transition is officially called Apple Silicon.
All of the features are still rolling in, but the next era in Mac hardware and software is here. Apple says that the first consumer Mac with Apple Silicon will be released by the end of this year and expect the transition to take two years. Both Microsoft and Adobe already are working on bringing Office and the Creative Cloud to Apple Silicon. Apple also already has built Final Cut Pro X for Apple Silicon.
To help with the transition, Rosetta returns with Rosetta 2 to help convert and emulate software to run on the new chipset. There will also be virtualization support.
For developers, there is a Developer Transition Kit that is a Mac Mini outfitted with an A12Z Bionic chip, which currently resides inside the 2020 iPad Pro. The kit costs developers $500 and they start shipping out next week. The developer must return the computer at some point in the future as well. This will help them develop their software for Apple silicon before the first consumer Mac with these chips are released this year.