Dihydropyridines end in -dipine
Dihydropyridines act in smooth muscles of blood vessels
Verapamil non-DHP works on the heart
-dipine Dihydropyridine target blood vessels
Antidote for calcium channel blocker is beta 1 adrenergic agonist or drugs to increase calcium ions
Verapamil targets the heart more than diltiazem
Diltiazem target vessels more than the heart, but works on both
Calcium channel blockers end in -pine Think of pine trees in California 
Dihydropyridine target smooth muscle
Non-dihydropyridine target heart
Used for hypertension, angina, and supraventricular arrhythmias