An electrical schematic is a diagram that shows how all of the wires and components in an electronic circuit are connected. They’re like a map for building or troubleshooting circuits, and can tell you almost everything you need to know to understand how a circuit works.
A collection of circuits with schematics and instructions for a wide range of fun and interesting projects: Circuits with transistors, 555 Timers, LEDs, +++
CircuitLab provides online, in-browser tools for schematic capture and circuit simulation. These tools allow students, hobbyists, and professional engineers to design and analyze analog and digital systems before ever building a prototype.