Let's start with:
I understand that only links are stored in Organizer, not the "real" files.
What's a link? It's the location (drive identification plus folder path) written in a file (a database, but that would be the same with an Excel or Word document, or even in a plain paper notebook).
If the catalog stores a location and you change the location, the link is wrong. Simple?
If I have to do some major reorganizing of my pictures in Windows, all the work I have done in creating albums, etc. in Organizer becomes worthless.
Why? Of course it is if you continue to destroy your own organization by moving, renaming or deleting files from the Explorer.
The organizer can do the major reorganizing itself. Instead of using the Explorer, you do the same tasks (moving, renaming, deleting...) while updating the links in the catalog. You have noticed that the 'Folders' tree panel on the left looks like the Explorer and has the same functions. As a matter of fact, the organizer transmits your organization orders to the routines of the Explorer.
But that's not all.
The huge advantage of a catalog organization like the Organizer or Lightroom is that the reorganization works on the catalog with its multiple indexes and keywords hierarchies without needing any move in the structure shown by the Explorer. I don't say the 'physical' structure of files on the drive, you know that it's hidden by the Explorer. There is nothing looking like folders or subfolders in the physical location of your picture files (each file may even be scattered in pieces in various disk sectors).
Just to give an idea of this advantage. With the organizer I can retrieve in a few seconds a dozen pictures having a given word in the middle of a caption and a date taken range, taken with a given camera searching from my library of 70 000 items. Try that with the explorer.
Another example: it's also possible to add a keyword to half of the items of my library in seconds, and to remove them as quickly. Try that with the explorer. Even searching a file name in the explorer may be very long, even if the Explorer also allows some sort of 'indexing' for file names.
Another example: you are used to Google searches by entering significant words: the text search of the organizer works the same. That's how you can find a given word in a keyword, in a caption or a note.
I am ready to discuss your other questions, but the above is necessary to start successfully.
Thank you so much for taking the time to answer my questions.
It looks like my main problem is that I'm still a beginner and we just got Photoshop and Light Room 3 weeks ago. Yes, windows 10 has a few tricks for organizing pictures, but Light Room and Photoshop Organizer appear to have a LOT of tricks available. I've talked to some of my photographer friends and they told me to look at the tutorials on Light Room because they import their pictures into Light Room and that gives them the ability to identify duplicates and delete the ones they don't like. Heretofore, my 18,000 pictures were imported using Windows tools, and that's probably why they are so messed up. When I imported them from the camera chip using Windows, they were put in one file, no matter what the subject of the photos were. I figured I would "sort them out later" and drag and drop them into properly named folders. It just got away from me and never got done. I'll report back after I've gotten more experience with Light Room.
Organizing with Lightroom or the Organizer is pretty similar.
I would recomend to post in the Lightroom for beginners forum:
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Also, my preferred source of info for Lightroom:
Download the free Lightroom eBook.