The general definition of an alarm clock is a time-telling device that can be set to make a certain noise at the desired time. Alarm clocks are usually used by people who need to wake up at a particular time. The traditional form of the clock was circular in shape and featured two bells on the top, with a large face and second, minute and hour hands.
If set correctly, the clock will make a certain sound at the set time, penetrating sleep and causing the person to wake. Many devices stop automatically after a particular period of time. It is also possible to shut off the sound by pressing a handle or a button on the device.
Many modern alarm mechanisms come complete with a snooze button. Pushing this button will shut off the alarm temporarily. The alarm will ring again after a short period, usually after three and five minutes.
The beauty of this snooze button is that it allows heavy sleepers a little longer to wake up. The only drawback with this feature is that people sometimes hit the off button by mistake. This can mean that they end up sleeping far more than they originally intended.
While the devices originally ran on clockwork, special electronic versions are available these days with way too many features. Many newer models come complete with a range of different alarms. This allows the users to select the sound that they want to wake up to.
Some versions also come complete with a radio. It is possible to program the radio to start playing at a certain time. This means that users can wake to the sounds of their favorite station. Listening to music in the morning is a great way to get the day started.
It is even possible to find devices that come complete with a television. This is ideal for people who enjoy watching television in bed. Some people may want to set their alarm so that they can watch their favorite morning show before they get up.