You will learn about two very important circuit elements - diodes1 and transistors. These elements make the world of digital electronics "tick". Digital electronics has revolutionized industry over the last 40 years. In the second half of this course, you will learn some of the fundamental concepts (Boolean algebra, microcontrollers, processor I/O and digital systems interfacing) behind this revolution. However, before you do so, you should understand the two devices - diodes and transistors - that were responsible for this revolution.