Hardware

Breadboards are designed to make quick electrical connections. Any electrical component can be connected to another electrical component through the rows and columns of a breadboard. Green encircles the manner in which connections can be made.

Typically the horizontal rows are designed to connect anything at a constant high voltage (+) or at a constant low voltage (-). These are often called busses.

The vertical columns are designed to connect other components. Note those connections don't cross the center.