I wanted to know is this a sample or population. I want to solve for the standard deviation, but I am not sure what it is. Personally I think it is a sample.These are the numbers of wins for the 30 NBA teams for the 2004-2005 NBA season.

45 43 42 33 33 54 47 44 42 30 59 45 36 18 13 52 49 44 27 26 62 50 37 34 34 59 58 51 45 18

That looks like a list of the number of wins for all NBA teams, which would make it a (total) population. If you listed the number of wins for fewer teams, you would be sampling.

To compute the standard deviation, average the squares of the deviation from the mean, and take the square root of that. The mean is 41 (half the number of games played per team).