Determine whether the following series converge absolutely, converge conditionally, or diverge.

∑(n=1,∞) (-1)^n/n√n

∑(n=1,∞) [(-1)^(n-1)][n/n(^2)+1]

My textbook has pretty sparse information in this chapter and I'm really having some trouble understanding the examples. What is the difference between series that converge conditionally and absolutely?