An alarm clock is an essential gadget for most people to get up in time for work or school. Some people prefer a classic alarm clock that they can place on their beside table while others use the alarm function in their mobile phone. Simply enter the time you want to wake up and the alarm will sound to get you out of bed. If you are not ready to bound out of bed you can always press the snooze function. Most alarm clocks have the same functions, often it is the design or sound that differentiates them.