What are multifocal eyeglasses? and what's the difference between multifocal and bifocal eyeglasses? Which one should I choose if this is my first time to wear eyeglasses?

Multifocal eyeglasses, also know as "invisible bifocal glasses", they can give you the intermediate distances that a regular bifocal lens can not do, and will feel more like you have normal vision if you wear this kind of progressive eyeglasses, so if this is your first time to wear glasses, I suggest you the invisible bifocal eyeglasses!

So, can you tell me where can I get discount progressive eyeglasses, I have heard this kind of lenses are much more expensive than bifocal ones, how much should I need to pay for? $150 or even more?