Everything LaTeX numbers for you has a counter associated with
it. The name of the counter is often the same as the name of the
environment or command associated with the number, except that the
counter’s name has no backslash \. Thus, associated with
the \chapter command is the chapter counter that keeps
track of the chapter number.
Below is a list of the counters used in LaTeX’s standard document classes to control numbering.
part paragraph figure enumi chapter subparagraph table enumii section page footnote enumiii subsection equation mpfootnote enumiv subsubsection
The mpfootnote counter is used by the \footnote command
inside of a minipage (see minipage). The counters enumi
through enumiv are used in the enumerate environment, for
up to four levels of nesting (see enumerate).
Counters can have any integer value but they are typically positive.
New counters are created with \newcounter. See \newcounter: Allocating a counter.