All of the currently defined columns are listed in this dialog. You can simultaneously edit the properties of all the columns you select. However, if you choose a mixture of Calculated Columns and Manual Columns, these will be edited in separate batches.
Keep in mind that Column Names must be unique within a data set. That is, if you select Column A, B, and C from the same data set, the Column Name field will be disabled to preserve uniqueness. On the other hand, if you select Column A, which exists in multiple data sets, the Column Name field will be active and you can change the name of the column. The name will be changed in all data sets.