Need help to describe a circuit

[Namek]

So, i was building a USB-oscilloscope with an assembly kit and I have to do a presentation for our school. I have a circuit but i don't really know what to say about it on the presentation. Could anyone please help me describe the circuit for the audience.

 

[AnalogKid]

A relay to select AC or DC input coupling
An input attenuator string with a multiplexer IC acting as an electronic rotary switch
A gain stage
A -1.1 V converter
A PIC uC acting as a digitizer, display formatter, and USB interface driver
A Cockroft-Walton charge pump converting +5 V to -5 V
A 3.3 V power supply

ak