· ·middle dot, interpunct

The middle dot (a.k.a. interpunct) is often used as a list separator, or in e.g. dictionaries for separating parts of a word (though in Unicode that is technically a different, but most often identical looking character: ‧).

To produce a middle dot character:

Windows

Alt 0183 (on the numerical keyboard, with Num lock on)

OS X

⌥ Opt . or
⌥ Opt ⇧ Shift . or
⌥ Opt ⇧ Shift 9 (depending on keyboard layout)

Linux

AltGr . or
⎄ Compose ^ . or
Ctrl ⇧ Shift u 00b7 ⏎ Return (or Space)

HTML

· · ·

L^aT_eX

\textperiodcentered

Unicode

U+00B7

Similar characters: hyphenation point, ‧ (separating parts of a word in e.g. a dictionary); multiplication sign, ⋅; Greek interpunct (άνω τελεία, áno teleía), ·; bullet, •; Japanese interpunct (中黒, nakaguro), ・