How does Passport deal with deletions and reanaming of files on computer?

I hope this is the right place for this question; I haven’t found it asked anywhere.
Background: One use of the WD external drive is to free up space on the hard drive of a computer by storing rarely-used files and folders on the WD external drive. If automatic backup is used, the WD device will save new files and folders that are added to the computer; it also will record changes to documents.
Sometimes I might decide that one or more files or folders that I haven’t been using really belongs on the WD drive only, to free up space on my computer.
The question is: If I have a number of files and folders on my computer, and those files and folders are also present in WD external drive, and I delete or rename a file or folder on the computer, will the WD external drive retain that file or folder, or delete or rename it?

Hello,

If you delete a file or folder from you computer that’s already backed up using WD Smartware this file or folder will not be deleted from the external drive.

If you rename a file or folder WD Smartware will recognize it as a new file and will add it to the backup.

Thank you!
So this means that over time, as I delete and/or rename items on my computer, the WD external drive will accumulate more files and folders?
Does the WD drive make any note of which ones were deleted and/or renamed on the computer drive?
I ask because I could foresee a buildup of irrelevant stuff that will be hard to weed out later. I do a lot of photo and video editing and this leads to a lot of files being altered, renamed and deleted.