Understanding Amplitude Modulation for Radios

[MadmanMurray]

I'm learning about radios at the moment but there's a few things I'm not clear about concerning modulation. I'll use audio amplitude modulation as an example. Let's say I have a device which I speak into and this device converts the variations of the sounds waves coming outta my mouth into an electrical signal which varies in amplitude in a wire. This wire is attached to an antenna which converts the electrical signal into a radio signal.

Is everything I described there amplitude modulation or am I missing something? I keep reading about 2 signals being merged and that there's a difference between the modulating signal and the carrier signal. Is the carrier signal a separate signal of the desired frequency? For example if my sound converting device converts my sound waves into an electrical signal which varies in amplitude would the frequency be varying and chaotic meaning I would need to merge it with a carrier signal of fixed frequency? Is that the general idea?

 

[jtbell]

Does the following help?

http://hyperphysics.phy-astr.gsu.edu/Hbase/audio/bcast.html#c3