An alarm clock is a device designed to wake people up at a specific time. It typically features a clock face or digital display that shows the current time, along with buttons to set the desired wake-up time. Many alarm clocks also have additional features, such as snooze functions, radio, or nature sounds to make waking up more pleasant. Most alarm clocks operate on electricity, but some can run on batteries, making them portable. They can be found in various styles, from traditional analog models with bells to modern digital versions with advanced features. Some even connect to smartphones or smart home systems for added convenience.