What is the result of $2^{{2}^{{2}^{{2}^{0}}}}$? What is the result of $2^{{2}^{{2}^{{2}^{0}}}}$?
It seems simple but I don't understand it.
Edit: Whoever is down-voting, please leave a comment as to why...

$$2^0=1$$
$$2^{2^0}=2^1=2$$
$$2^{2^{2^0}}=2^2=4$$
$$2^{2^{2^{2^0}}}=2^4=16$$
