How to Identify and Analyze an Unknown Electronic Circuit from a Schematic

what does that circuit name? I need to analyze it ..

What's RIN1 AND RIN2 AND ROUT?!!!! rin1 is the resistance that we see from V1 , rin2 is the resistance that we see from the V2 ..

Hi Ryan-The whole circuit is an operational amplifier.Q1 and Q2 form a current mirror.  For some references about this, look here: Analog Devices Wiki Chapter 11. See section 11.6.  Q5 and Q6 form a second current mirror being fed by a differential pair of Mosfets.RIN1 and RIN2 will be very high impedance and Rout will be a relatively low impedance.  These values will be determined by the characteristics of the MOSFETS.  I don't have the formulas to calculate these values at my fingertips, but I'll bet they're on the Analog Devices Wiki.-Rick 

The whole circuit is a differential amplifier, which can be used as the input stage of an operational amplifier. Note that Vout must always be more negative than Vin2 for linear operation.
To make an operational amplifier, Vout would drive a level-shifting gain stage built with an N-channel MOSFET to shift the level positively. This would in turn drive an output buffer stage.