question about Radio contol systems?

Im building a model which is not the normal type of radio control model
I want 4 electric motors that I can have running at variable speed from slow to full speed .. and to be able to run them in reverse also… and to be able to run each independently
Im new to RC modeling and just starting to research it

My question is, in models that use electric motors that already exist, such as airplanes and helicoptors… is the motot usualy controlled from the RC reciever directly or ..
Does the motor get its power from a potentiometer or varaible rsistor which is adjusted by a servo whicjh in turn conects to the RC reciever

Also.. does anyone know any good web pages where I can learn more ?
I have found http://www.rc-airplane-world.com/radio-control-gear.html which seems to be informative but wpould welcome other links

Thank you

The e-motors are controlled by an ESC (electronic speed controller). An ESC can control multiple motors, but they cannot work independently. You could use multiple ESCs, but the problem is that the power is going through the ESC to the Rx. Although, you can have 4 ESCs, each having it's own battery and use the Rx only for the signal channel.

What exactly do you want to build?

If you have anymore questions or if you need any tip, e-mail me. I just want to make sure that beginners learn the right things.