To get up and running, you just need a Mac with an internet connection. There are a handful of minimum requirements, but ...

The Mac's DMG format is similar to the ISO format on Windows, which can be used to mount virtual volumes, clone entire discs, and much more. It's a common way to distribute Mac apps online.

Apple’s macOS 15.1 Sequoia now lets you install and use applications acquired from the Mac App Store directly onto an external drive.