What does Z_2^5 mean in linear algebra notation?

[TysonM8]

I know how to solve linear systems but I came across this question where I've never seen the notation before. I searched all over the internet but still couldn't figure it out. The question asked to find all solutions in Z_{2}^{5} of a linear system. I'm guessing that Z^5 means all integers on R^5 since there were 5 variables in the linear system, but I don't know what the subscript 2 means. Anyone care to explain?

 

[pwsnafu]

$\mathbb{Z}_2$ usually means modulo 2. In English it means you are only interested in whether a number is even or odd.