The tag 'chase' is only used once. This is the project:
16 LED Hookup w/chase sequence
16 LEDS connected to the breadboard, each LED is routed back to a digital pin on the Arduino which can be programmed to light in a variety of sequences
Items Required: x16 10k Ohm Resistor/ x16 5mm LEDs/Various lengths of solid core hookup wire/Arduino/Breadboard