1. Physical layer:
   --> Domain of EE
   --> Why study it? Allows you to open up the blackbox
2. First question: translating bits to voltages
   --> Quantization
   --> Signal-to-noise ratio
   --> The Shannon-Hartley theorem
   --> Finding the right level of quantization
   --> Sources of errors: attenuation, multipath, interference
3. Second question: transmitting these voltages
   --> Message signal and carrier signal
   --> Sinusoisoidal vs. square wave carriers
   --> FM
   --> AM
   --> PAM
4. Third question: Detecting and correcting errors
   --> Similar to the md5sum algorithm
   --> Parity bit: one bit error but no more. Can't catch two-bit errors
   --> Used in UART to communicate from host to microcontroller