PCT contains a list of valid transaction ID.
Each transaction ID is paired with the name of the program ,CICS will load and
execute when the transaction is invoked.
On the other hand, PPT indicates each
program's location which pertains to a storage address if the program has
already been loaded or a disk location if the program hasn't been loaded. PPT
will also be used to determine whether it will load a new copy of the program
when the transaction is invoked.