Apple File System

Apple File System (APFS) is a proprietary drive format system that Apple introduced in MacOS 10.13 "High Sierra" in 2017. It was also adopted in iOS 10.3, tvOS 10.2, and watchOS 3.2.

Features
APFS is designed to accommodate the use of solid-state drive storage across Apple's product line and address shortcomings of the long-used HFS Plus (Mac OS Extended) drive format, such as the 2040 date limit. .

APFS-formatted drives are partitioned into "containers" in which individual volumes are assigned specific roles. Volumes with preboot, recovery, and virtual memory (VM) roles are not mounted and remain hidden by default. Starting with macOS Catalina, volumes can be organized into "volume groups" where the bootable macOS system and data are kept in separate volumes and the system is kept locked by default. The purpose of this separation is to protect the macOS system from modification by hackers.