How do cephalopods catch and eat their prey?

Cephalopods have suckers on their tentacles with which to grab onto their prey.  They then have what is known as a radula, otherwise known as a rasp tongue, with which they rasp their food into pieces so they can easily swallow it.  They also have a special beak that is used to cut up their prey and to crush the shell of the crustaceans they capture.  Octopuses have a slightly different method, known as external digestion.  They still crack open the shell of their prey, but they then secrete a digestive liquid onto the organs of their prey in order to paralyze it and liquefy the innards.  The octopus then sucks up the liquefied organs.