A library is a component meant to be consumed either by:
A library is also known as a package. (
not to confound with the term package that may be refer to the scope/directory of a script
)
Library are reusable software components that encapsulate solutions to common problems.
Telling a programmer there's already a library to do X is like telling a songwriter there's already a song about love.
When the library is ready to be reused by other library, you distribute it
A library manager helps to:
A library manager is also known under the term package manager. See Code Shipping - (Package|Library|Dependency) Manager
library are published, shared and available for consumption in a remote location called a repository.
A repository may be local on your computer but it has a cache function and is only available to yourself