Please explain negative exponents

Question

How do you simplify when you have negative exponents? 

What is a "0" exponent - do I assume it is like "x" to the first power?

Answer 1

a^-1 = 1/a¹
a^-2 = 1/a²
a^-3 = 1/a³
.............
a^-n = 1/aⁿ

a⁰ = 1

a1 = a
a² = a*a a³ = a*a*a
..........
aⁿ = a*a*a*  ....  *a 
        ↑  "n"  times   ↑