A personal alarm is a small, portable device designed to emit a loud sound when activated. It is often used for personal safety, helping to deter potential attackers or alert others in case of an emergency. Many personal alarms are compact and can easily fit in a pocket or attach to a keychain, making them convenient for everyday carry. These alarms typically work by pulling a pin or pressing a button, producing a sound that can reach up to 130 decibels. Some models also include features like a flashlight or a built-in whistle. Personal alarms are popular among individuals such as students, joggers, and elderly people for added security.