The Arduino Board:

Looks like this...

Things to notice about the board: The long black thing in the lower right is the brain of the operation -- the microprocesor. The shiny square connector (USB power port) is how you talk to your Arduino and provide power from your computer. The cylindrical object at the bottom left is a connector that allows you to connect a battery (usually a 9V battery) to power the Arduino remotely. We will be using this port.

Power Ports:

Viewed from the end....

The port on the left (squarish) is the one your power/communication cable plugs into. For most Arduino's the power cable looks like this...

Some models of Arduino use a micro or mini USB for the power end that connects at the Arduino.

When you plug the cable into both the Arduino AND your computer it will look something like this...

 

This is how most folks connect their Arduinos in the beginning. Later on they will often be further from the computer because we'll be connecting them to other electronics.