[Free Registration/Login may be required to access all resource tools.] Covers electronic signal, how an electric current can be used to send an electronic message, what analog and digital signals are, and the difference between them.

Learn how electricity flows through a circuit by watching how the electrons move.

Online, college-level course on electronics. Class features the practical introduction to electronics with a focus on measurement and signals. Accessible components include downloadable lecture notes, assignments, and previous quiz and...

Why do the lights turn on in a room as soon as you flip a switch? Flip the switch and watch the electrons. Does the light turn on immediately? Explain using observations of the model.

Hammerhead sharks are recognizable for their bizarre head shape which is thought to make the shark more sensitive to electrical signals used to detect hidden prey. There are ten species of hammerhead. Learn more about hammerhead sharks...

Have you heard of a disease called Parkinson's? When people have this disease they often show signs or symptoms, like shaking uncontrollably. This shaking can make doing simple things harder. Emma Lawton is a person with Parkinson's, and...

See how electrical and chemical signals are used by neurons to communicate with one another at synapse contact points. [1:09]

A collection of video lectures from a course introducing students to the theory and practices in digital communications. Webpage includes twenty-four lectures from a professor at the Massachusetts Institute of Technology. Lectures vary...

This site contains a straightforward definition of resonance in an electrical circuit.

Your timing made you and your partner infamous bank robbers. Now, you need to use that timing to break out of jail. Your partner is about to flash you a signal, and exactly 45 seconds later the electric fence circuit will short out. Then...