Film Capacitor Selection: DC Link, Snubber and Class X/Y Safety Caps
Film capacitors get chosen last and specified least. They are the part you reach for when a ceramic loses most of its capacitance under bias and an electrolytic will not survive the ripple, and the three jobs they usually do, mains suppression, DC link and snubber, have almost nothing in common beyond the dielectric. Picking one means answering a different question in each case.
Passive Components