What are the applications of Thevnin Norton and Maximum Power Transfer Theorem?

Norton's and Thevenin's Theorems are used to simplify complicated linear circuits. They're applicable in any case one would like to simplify a messy linear circuit that is not already in Thevenin or Norton form.

Maximum Power Transfer: "Practical applications of this might include radio transmitter final amplifier stage design (seeking to maximize power delivered to the antenna or transmission line), a grid tied inverter loading a solar array, or electric vehicle design (seeking to maximize power delivered to drive motor)."