adverb In, on, or at this place (a place perceived to be close to the speaker); compare there.
You wait here while I fetch my coat.
adverb At this point or stage (in a process, argument, narration, etc.)
I've had enough of peeling potatoes. I'm stopping here.
adverb In this matter.
You say that all men are born equal, but here I must disagree with you.
adverb Notionally at the speaker's location by virtue of happening now.
Flu season is here.
adverb In this context.
Derivatives can refer to anything that is derived from something else, but here they refer specifically to functions that give the slope of the tangent line to a curve.
adverb After the name of a person perceived as located close to the speaker, used familiarly to indicate that person.
Jim here has been with the company for twenty years.
adverb After certain determiners, especially 'this' and 'these', used to emphasise demonstrative sense; see also this here.
This here orange is too sour.
adverb To this place; used in place of the literary or archaic hither.