Here - is used when something or someone is close

    I want you to come here to see me.
    I am already here so let me see if they have to stuff I need.
    I called my friend to tell her that I am here.
    When you get here call me, and I will come outside to meet you.

There - is used when someone or something is not close or far

    If you are home I will come over there.
    Do you like living over there?
    What time is it over there in New York?

Note: Sometime here or there can be interchangeable (either word can be used)