Circuits are assemblies of electronic components. The flow of electricity through a circuit is described by Ohm's Law. Electricity flows through nodes, also called junctions, which are electrical connections between components. Nodes are made up of one or more branches, which are the the connections between the components that make up a node; branches and components are effectivly the same.
Video: Circuit Terminology
Deeper Knowledge on Electrical Circuits
Building blocks for electrical circuits
Broader Topics Related to Electrical Circuits
Build and deconstruct electrically powered devices
A formula for determining voltage, current, and resistance