indicative mood
Definition - The grammatical mood or form a verb takes to make factual statements.

1. It is the most commonly used mood, and it is found in all languages.

Example -
It is used:
(1) to make statements (You know him) and
(2) to ask questions (You know him?)

Etymology -
The word derives from the Latin indicitavus, stating, which was a translation of the Greek horistike.

Oxford English Dictionary -
Its first citation is from 1530:
"The indicative mode they use whan they shewe or tell a thyng to be done."
(Jehan Palsgrave, Lesclarcissement de la langue françoyse, 84)

Please comment