$\cdot$

\cdot

The center dot.

$\cdots$

\cdots

By adding an "s" to the command "\cdot", you can create multiple dots instead of a single dot.

$\ldots$

\ldots

The lower dot.

$\vdots$

\vdots

The vertical dots.

$\ddots$

\ddots

The diagonal dots.

$\dot{ a }$

\dot{ a }

By using the "\dot", you can place a small dot above a character.

$\ddot{ a }$

\ddot{ a }

By stacking the "d", you can add additional dots above the character. Each stacked "d" adds another dot, allowing you to create a sequence of up to four dots.