Macintosh HD

Macintosh HD has long been the default name for the internal hard drive or solid-state drive on Mac models.

History
The Macintosh HD icon has historically been present at the top right corner of the desktop of new Macintosh computers since classic Mac OS, though recent versions of macOS hides this from new users by default. When visible, double-clicking on it opens a zooming Finder window, which displays the files and folders stored in the drive. As of Mac OS X 10.4 "Tiger", the Macintosh HD icon also lies underneath the Network entry, and above the optical drive icon, in the Finder sidebar. This default name with "HD" still remains in use even though Apple products now use solid-state drives for internal storage.