External drives are essential tools for expanding storage, backing up data, and transferring files between different systems. In the macOS environment, using external drives is straightforward and offers several built-in tools to manage and optimize their use. This article will guide you through the process of connecting, formatting, and managing external drives on a Mac. We will also cover some useful Terminal commands for advanced users who prefer command-line interfaces.

Examples:

1. Connecting an External Drive:

   • Simply plug in the external drive into a USB, Thunderbolt, or FireWire port on your Mac.
   • The drive should automatically appear on your desktop and in the Finder sidebar.

2. Formatting an External Drive:

   • Open the Disk Utility application (found in Applications > Utilities).
   • Select the external drive from the list on the left.
   • Click on the "Erase" tab.
   • Choose a format (e.g., APFS for modern macOS versions, Mac OS Extended for older versions, or ExFAT for cross-platform compatibility).
   • Click "Erase" to format the drive.

3. Using Terminal to Manage External Drives:

   • Listing Drives:

     diskutil list

     This command lists all connected drives and their partitions.

   • Erasing a Drive:

     diskutil eraseDisk HFS+ ExternalDriveName /dev/disk2

     Replace "HFS+" with your desired format and "/dev/disk2" with the identifier of your external drive.

   • Mounting and Unmounting Drives:

     diskutil unmountDisk /dev/disk2
     diskutil mountDisk /dev/disk2

     These commands unmount and mount the drive, respectively.

4. Backing Up Data Using Time Machine:

   • Connect your external drive.
   • Open System Preferences and select "Time Machine."
   • Click "Select Backup Disk" and choose your external drive.
   • Time Machine will automatically back up your data at regular intervals.

5. Encrypting an External Drive:

   • Open Disk Utility.
   • Select the external drive and click "Erase."
   • Choose a format that supports encryption, like APFS (Encrypted).
   • Enter a password and click "Erase."