Extra Magic Hours called EMH mornings and evenings are part of a Disney programme which allows guests to visit a certain theme park on a certain day outside that park's regularly scheduled hours. You need to be staying at one of the following to take advantage of the programme:
Any Walt Disney World Resort
Walt Disney World Swan or Dolphin resort
Hilton Resort at Downtown Disney
Shades of Green
The 2008 Schedule can be found HERE
Morning Extra Magic Hour gives you one hour before the regular time so if it was EMH morning at the magic kingdom and it opened at 9am usually on that day, you would be allowed in at 8am
Evening Extra Magic Hours extend the parks opening times by three hours! So if it's an EMH evening at EPCOT and it's due to close at 9pm, you will be able to stay till 12am
Not ALL attractions are open during EMH and the ones that are vary.
You used to show resort ID and park ticket to get a wristband which would be checked before you got onto a ride. This system has now changed and now you must be able to show valid resort ID at any time in the park. TIP-putting your resort ID in a lanyard can help you keep it accessible at all times