Reddit reviews Design of Analog CMOS Integrated Circuits (Irwin Electronics & Computer Enginering)

Would probably be better to post this to r/ECE rather than to Hardware, but either way:

Shortly summarized:
A MOSFET is a 3-terminal device (4 if counting bulk, and there's also a 6T type), where you have Gate, Drain & Source. Assuming you know BJTs, you can "map" them as:

• BJT - MOSFET
  
• Base - Gate
  
• Collector - Drain
  
• Emitter - Source.
  
  If again, we're comparing MOSFETs to BJTs, we can say that a MOSFET is a VCCS (Voltage controlled current-source), while BJTs are CCCS (Current controlled current-source). In other words, when you apply a voltage to the gate of a MOSFET you'll create a current at the drain of the MOSFET. The current that's generated depends of the operating region:
  
  
• Subthreshold (Voltage over Gate-Source are less than the threshold voltage; Vgs < Vth)
  
• Linear/Triode region (Voltage over Gate-Source are more or less than threshold, but Voltage over Drain-Source are less than the Gate-Source voltage; Vgs >= Vth, Vds < Vgs)
  
• Saturation region (Voltage over Gate-Source are more or less than threshold, and voltage over Drain-Source are more than or equal to Gate-source voltage; Vgs >= Vth, Vds >= Vgs).
  
  Normally one operates in the the saturation region.
  
  Not sure how much details you want, but if you want to read more about MOSFETs you've got books such as Sedra & Smith or Razavi

https://www.amazon.co.uk/Integrated-Circuits-Electronics-Computer-Enginering/dp/0072524936/ref=sr_1_1?ie=UTF8&qid=1511563496&sr=8-1&keywords=razavi+analog