How to Read Voltage Level? I want to read voltage level by my Arduino board please help in this regard. I am using this syntax.

volts = analogRead(A3);    // read the input pin
Serial.println(volts)
First off you need to convert your signal's units from analog -> voltage. Do this by using the following equation. I've modified your code so you can copy and paste it into your IDE. 

float volts = analogRead(A3) * ( 5.0 / 1024.0) ; 


Hope this helps! Good luck!