Electronics

Tutorials

 * All About Circuits : Free Electric Circuits & Electronics Textbooks - http://www.allaboutcircuits.com/
 * Electrical/Electronic - Series Circuits - https://www.swtc.edu/Ag_Power/electrical/lecture/combo_circuits.htm
 * Lessons In Electric Circuits -- Volume I (DC) - Table of Contents - http://www.ibiblio.org/kuphaldt/electricCircuits/DC/index.html
 * basic electronics - http://www.electronics-tutorials.com/basics/basic-electronics.htm
 * Instructables Basic Electronics - http://www.instructables.com/id/Basic-Electronics/?ALLSTEPS
 * Beginning Embedded Electronics - SparkFun Electronics - https://www.sparkfun.com/tutorials/category/1


 * The Transistor Amplifier - http://www.talkingelectronics.com/projects/TheTransistorAmplifier/TheTransistorAmplifier-P1.html
 * Basic Electronics Tutorials and Revision - http://www.electronics-tutorials.ws/
 * Basic Electronics - https://www.clear.rice.edu/elec201/Book/basic_elec.html
 * basic electronics - http://www.electronics-tutorials.com/basics/basic-electronics.htm
 * Basic Electronics - http://101science.com/Radio.htm

Ohms Law
http://upload.wikimedia.org/math/a/3/d/a3ddbc2ec4f5974fb9d5b7ed9523c93e.png

Pull-up Resistor
The Basics - Very Basic Circuits - http://www.seattlerobotics.org/encoder/mar97/basics.html

current sources and sinks
Sinking and sourcing refer to the type of digital inputs and outputs used.


 * Sink: A sinking digital I/O (input/output) provides a ground.
 * Source: A sourcing digital I/O provides a voltage source.

References:
 * What Is the Difference Between the Terms Sinking and Sourcing? - National Instruments - http://digital.ni.com/public.nsf/allkb/A10122C63A7F5CFE86256B4C007491DD
 * Sinking vs. Sourcing - http://support.motioneng.com/hardware/io/slice-io/topic_sink_source.htm

Vcc
IC power supply pin - Wikipedia, the free encyclopedia - https://en.wikipedia.org/wiki/IC_power_supply_pin