memory faults - startup disk full but nothing to delete?

Wiping the drive is a drastic “solution" and won’t really solve anything since you’ll probably wind up in the same situation again. First, as you’ve noticed Apple has labeled some specific kinds of files: Music, Apps, Photos, etc. Other is simply anything that doesn’t fit under any of the specific categories. Second, Spotlight, the technology that keeps track of files, what kind of files they are, and so forth has a bug that all too often results in the Spotlight index file becoming damaged. Once that happens files lose their designation. This makes it look like “Other” is taking over the computer.

If you’d rather fix the problem than simple rinse and repeat you’ll need to do two things: 1) figure out what can be deleted or moved from the computer to an external drive and 2) reindex Spotlight so you have a more accurate sense of what’s on the computer.

OmniDiskSweeper is a free program that will catalog your hard drive and let you see what’s on it. Note 1 - never delete anything from the Library or System folders - they contain vital operating system files. The Library folder in your own drive space also holds important files. Removing the wrong one(s) can mess up your account, but not the computer. Don’t erase anything from it unless you know what you are doing. Note 2 - you can delete lots of document files and even apps without freeing up much space. The biggest files are music, video, and photos. Note 3 - Your computer has an incredibly small hard drive and it requires discipline to keep from filling it. You might want to consider replacing the SSD with a larger one. Check out OWC for availability, prices, and videos showing how to do the upgrade.

Here’s how to reindex Spotlight: Rebuild the Spotlight index on your Mac - Apple Support