One of the simple yet interesting connection diagrams that young engineers learn in their lab is the staircase lighting setup.

Arduino is a popular open-source development board used by engineers, hobbyists, and makers to develop electronic projects and prototypes easily.

A number sequence is a list of numbers that are linked by a rule. If you work out the rule, you can work out the next numbers in the sequence. In this example, the difference between each number is 6.