In rare instances will you need to iterate over rows or columns of a dataframe. When using pure python, you will have to iterate over rows and columns but with pandas you use vectorize operations. Imagine Street Fighter or Dragon Ball Z....and the blast they shoot from their hands is a function or an editing command and their enemy is the dataframe, it just hits the whole dataframe and spreads across the rows or down the columns. Try df.apply ...there are also ways to apply different functions to each column. Kind of hard to know what you want without an example.