You're going to use a string of LEDs (10 in total) to make an LED chase effect, similar to that used on the car KITT on Knight Rider or on the face of the Cylons in Battlestar Galactica. This project will introduce the concept of arrays.
10 5mm RED LEDs
10 Current Limiting Resistors
First, make sure your Arduino is powered off by unplugging it from the USB cable. Now, use your breadboard, LEDs, resistors, and wires to connect everything as shown in Figure ...