Hi,
Something went wrong with attaching the image, refer to:
How to Attach a File to a Post
Libraries are nothing more than folders with DXF/DWG snippets, Script items and so on.
The libraries collection can become vast while you only need a limited selection of library items in your current project.
It is the idea that you only include the required items in a drawing file.
Like borrowing a few books from the vast collection of books in a public library instead of all the books.
Also refer to the tutorial:
Working with the Part Library
See the Library Browser as a specialized File Explorer / Finder that generates a preview of DXF/DWG files.
When included correctly in the folder structure your parts should show up in the Library Browser.
What is not shown in this tutorial is that a copy of the part is included in the Block List on inserting a part as Block.
Besides the copy as Block (definition) a Block Reference is placed in the drawing at the indicated position.
Additional Block References based on the same Block can now be inserted at various places.
Remind that it is an unrelated copy of the library item current art.
Changes made to a library part afterwards are not reflected back into existent Blocks based on that library part.
Nor are changes applied to the Block content reflected back to the original library part.
Regards,
CVH