The question then is:
If you don't know what "Other" is, and you don't know where "Other" is, how do you know it is not something you need to keep?
You will discover if you search around on your storage drive that no files or documents are identified as "Other" but are simply called what they are.
"Other", for Storage purposes, is simply everything that is not included in the other categories (Apps, Audio, Photos, Movies, and Backups). It's just a general designation that the system uses, but isn't necessarily tied to anything.
"Other" can be your system files, your documents and other data files, and several other possibilities.
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The problem is that storage chart is notoriously inaccurate. You could get a better picture of what you have by rebuilding your Spotlight database. That will then likely show you a more accurate chart, but the chart will simply go off again after some time.
Better - would be to use one of the techniques in the various threads here that cover "how do I find out what is using the space on my Mac", or something similar. That will help you decide which large files you have, and you can decide if you need to keep them. And, you can come back here if you have some question about what to keep (and what to remove

)