The \DeclareCaption command defines a class of caption command
associated with the counter specified to the command.  These commands
are free-standing (i.e., don't need to be inside a float environment).
The package uses \DeclareCaption to define \figcaption and
\tabcaption, which can be used outside figure or table environments.

Homepage:
https://www.tug.org/texlive/
