did_	SCOP domain identifier
pdb	PDB identifier for the PDB protein this domain is a part of
sel	chain (on range of residues on a chain) of PDB protein which make up this domain
fids	hierarchical identifier of the following form:

root.class.fold.superfamily.family.species/protein

Note that root is always 1 and that these numbers change from one scop version
to another.