1. conjunction /ʍɛə(ɹ),wɛɹ,ʍɛɹ/
Where Susy has trouble coloring inside the lines, Johnny has already mastered shading.
b) At or in which place or situation.
He is looking for a house where he can have a complete office.
2. adverb /ʍɛə(ɹ),wɛɹ,ʍɛɹ/
a) (used interrogatively, in either a direct or indirect question) At what place; to what place; what place.
Where are you?
b) In what situation.
Where are you going?
3. pronoun /ʍɛə(ɹ),wɛɹ,ʍɛɹ/
The place in which.
He lives within five miles of where he was born.
4. noun /ʍɛə(ɹ),wɛɹ,ʍɛɹ/
A good article will cover the who, the what, the when, the where, the why and the how.
Wikipedia foundation.