Libraries
Navigating Library Panels - http://techdocs.altium.com/display/ADRR/IntegratedLibrary_Pnl-Libraries((Libraries))_AD
The Definition of a Component and Component Parameters
https://techdocs.altium.com/display/ADOH/Component,+Model+and+Library+Concepts
Summary and Definitions
Creating a Component
Schematic Component (Logical/Graphical representation of a component on the schematic)
PCB Footprint (Physical representation of the space taken up by a component on the PCB)
https://techdocs.altium.com/display/ADOH/Creating+Library+Components
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+Tutorial#CreatingLibraryComponentsTutorial-ManuallyCreatingaFootprint
More Details on Libraries and Components - https://techdocs.altium.com/display/ADOH/Library+and+Component+Management