Column parameters allow a column and its associated table and dataset to be specified as a single parameter, using a colon-separated triple, of the form set:table:column.
For example:
foo.FITS:R1SPE1:CCDNODE # Column CCDNODE in table R1SPE1 in set foo.FITS
The SAS GUI allows a column to be selected in a single operation, using a dataset browser. This is simpler than entering 3 separate parameters for the dataset, table and column.