Operating Systems

APFS

Definition

The Apple File System (APFS) is a proprietary file system for macOS, iOS, iPadOS, tvOS and watchOS, developed and deployed by Apple Inc.

Why It Matters

APFS is optimized for modern flash and solid-state drive (SSD) storage. It includes features like strong encryption, space sharing, snapshots for backups, and faster file copying.

Contextual Example

When you update macOS, the system can create a "snapshot" of the file system. If the update fails, it can instantly revert back to the snapshot, making the process much safer.

Common Misunderstandings

  • One of its key features is "cloning," which allows the OS to make a copy of a file or directory almost instantly without using extra storage space until changes are made.
  • APFS replaced the long-standing HFS+ as the default file system for Apple devices.

Related Terms

Last Updated: December 17, 2025