The columns are separated by the tab key, i.e., "\t", so that you can easily import the data into MySQL database with command like this:

The columns are (from left to right):
01	3-letter Ligand ID, which follows the Chemical Component Dictionary (CCD) used by the PDB database
02	Chemical formula
03	InChI
04	InChIKey
05      SMILES string. Multiple SMILES strings are separated by semicolons
06	Name. Multiple names are separated by semicolons
07	ChEBI ID
08	DrugBank ID
09	ZINC ID