Glossary

Your Mac's built-in disk is the storage inside the Mac itself, which holds macOS, your apps and your files. Storage Studio's job is to keep room free on it.

An external drive is a drive you plug into your Mac rather than one built in. It is where Storage Studio moves folders and apps to free space on your Mac.

A shortcut, or symbolic link, is a tiny file that points to a file or folder somewhere else. Storage Studio leaves shortcuts behind so moved things still open from their old place.

In Storage Studio, a move means copy, check, then remove the original, in that order. The original is never removed until the copy has finished and been checked.

To relocate is to move something to your external drive and leave a shortcut in its old place, so it still appears, and opens, where it always did.

Offloading an app packs the app and its data into an archive on your external drive and removes them from your Mac. It can't be opened until you restore it.

An online-only file lives in a cloud account, with only a placeholder on your Mac. It still shows in Finder and downloads when you open it.

A cache is data an app keeps so it can work faster next time, and can rebuild by itself if it's removed. Storage Studio clears only recognised cache folders.

Purgeable space is room macOS is using for things it can clear by itself when it needs the space, such as local snapshots. It counts as available, but isn't empty yet.

A local snapshot is a point-in-time record of your disk that macOS keeps on the disk itself, mainly for Time Machine. It can hold on to space from files you've since deleted.

APFS (Apple File System) is the format Macs use for their disks. It is the recommended format for the external drive you use with Storage Studio.

exFAT is a drive format that both Macs and Windows PCs can use. It can't hold Mac permissions, access lists or hard links, so APFS is recommended for Storage Studio.

Extended attributes are small pieces of extra information attached to a file, such as its Finder tags or where it was downloaded from. Folder moves keep them.

Finder tags are the coloured labels and named tags you give files and folders in Finder. A folder move between your Mac and your external drive keeps them.

An access list (ACL) is a set of extra permission rules on a file or folder, beyond its basic permissions. Storage Studio keeps them only where the drive can hold them.

The Locked flag is the Locked checkbox in a file's Get Info window, which stops it being changed or deleted. Storage Studio carries it over to the moved copy.

A hard link is a second name for the same file on the same disk, so its contents are stored only once. Folder moves keep hard links as links.

A sparse file has long empty stretches that the disk doesn't actually store, so it takes less space than its size suggests. Folder moves keep it sparse.

Every file on a Mac records which user owns it. External drives normally ignore ownership, and Storage Studio doesn't keep it when moving to one.

Two-way sync keeps two places the same by copying changes in either direction. In Data Transfers it is called Bidirectional sync.

One-way sync makes a destination an exact mirror of a source, including deleting files at the destination that aren't in the source.

A dry run is a rehearsal: it shows what an action would do without changing anything. Storage Studio offers one for transfers and for automatic moves.

An incremental backup copies everything once, then saves only what has changed each time after. Data Backup works this way.

A backup version is a saved point in time you can restore from. Data Backup keeps a series of versions for each backup set.

Full Disk Access is a macOS privacy permission that lets an app read files in protected places. Storage Studio asks for it so it can see and move what uses your space.

Apple silicon is Apple's own family of Mac chips, the M-series. Storage Studio 4.18 and later need a Mac with Apple silicon; Intel Macs stay on version 4.17.1.

An app's safety level is Storage Studio's rating of how safely it can be moved to your external drive: Safe, Caveat, Override or Blocked.

A verified copy is one Storage Studio has checked against the original before removing the original. How thoroughly it checks is up to you.