component Definition
Specifies the ports (pinstubs) of a logic function in VHDL. A component, which consists of the name of a logic function and a list of the function's inputs and outputs, is specified in a Component Declaration and is often stored in a package.
The 
                     Quartus® Prime software includes a variety of megafunctions
                  and primitives that are supported by VHDL and are automatically
                  installed in the subdirectories of the
                  \quartus\libraries\vhdl directory. Components for these
                  logic functions are provided in the maxplus2 and
                  megacore packages in the altera library, the
                  altera_mf_components package in the altera_mf
                  library, and the lpm_components package, available in
                  the lpm_pack.vhd file, in
                  the lpm library.
               
In a VHDL Design File (.vhd), you can use a Component Instantiation Statement to insert an instance of a logic function that is defined as a component in a Component Declaration.