Disks & storage

Adjust the size of a filesystem — Shrink or grow a filesystem and its partition.
Check how much disk space is left — Use Disk Usage Analyzer, System Monitor, or Usage to check space and capacity.
Check your hard disk for problems — Test your hard disk for problems to make sure that it’s healthy.
Manage volumes and partitions — Understand what volumes and partitions are and use the disk utility to manage them.
Repair a damaged filesystem — Check if a filesystem is damaged and bring it back into a usable state.
Test the performance of your hard disk — Run benchmarks on your hard disk to check how fast it is.
Wipe everything off a removable disk — Remove all of the files and folders from an external hard disk or USB flash drive by formatting it.