TomOakhill:
What voltage, wattage, and current can the pins sense?
What does ICSP, PWM, Communication mean?
How do the RX, TX, and L light emitting diodes differ? What do they signal?Please point me to the document. Thanks Tom
A single document won't help, instead a library is required for your studies.
Start with electric, electronic and maths fundamentals, advance to logic and boolean algebra, digital and analog electronic circuits, communication theory, only to name a few basic topics you should know in order to understand the answers to your questions.
But I assume that you only are trolling, by enumerating a number of buzzwords. Can you enumerate also your skills in above areas?
Or simply get an Arduino Starter Kit and start exploring that mysterious land yourself.