Many of the functions that you just learned to use with Panda's data frames also work when you're specifically pointing toward a series within that data frame. So for example, head, which shows you the first rows tail, which shows you the ending rows and min and max. So here I can see the first row of series three, the last row of series three, the min of series one and the max of series one. For categorical or non-numerical values in a panda's data frame. It can be useful to find the unique values in that series. You can do that using the unique function like we have right here. I'm looking at industry data frame and the series called sector, and then I'm calling the unique function. This can be a good way to identify, for example, different sectors in a portfolio or like we have right here. It can be a good way to identify spelling errors or other different errors in your dataset.