Apple MacBook Air (13-inch, Late 2010) - Manual (Page 11)

11 Chapter 1 Ready, Set Up, Go
To extend the reach of your power adapter, replace the AC plug with the included AC
power cord. First pull the AC plug up to remove it from the adapter, and then attach
the AC power cord to the adapter, making sure it is seated firmly. Plug the other end
into a power outlet.
When disconnecting the power adapter from an outlet or from your MacBook Air,
pull the plug, not the cord.
When you connect the power adapter to your MacBook Air, the indicator light on
the MagSafe connector starts to glow. An amber light indicates that the battery is
charging. A green light indicates that the battery is fully charged. If you don’t see a
light, make sure the connector is seated properly and the power adapter is plugged
into a working power outlet.