What are various possible circuit analysis that can be implemented in SPICE?

In declarartion of MOSFET other than the essential parameters of length and breadth, what are the other parameters supported by SPICE?

A pulse voltage source is defined from 0 to VDD with 100ps delay, 100ps rise time, 100ps fall time, 2n pulse width, and 4ns repetition period.Write the declaration for such a source in SPICE?

What is the basic unit in Spice coding?