A phone number is a unique sequence of digits assigned to a telephone line, allowing individuals to make and receive calls. It typically consists of an area code, which identifies a specific geographic region, followed by a local number. Phone numbers can be used for landlines, mobile phones, and other communication devices. Phone numbers are essential for communication in today's world, enabling people to connect with friends, family, and businesses. They can also be used for text messaging and various online services. In many countries, phone numbers are formatted in a standardized way to ensure consistency and ease of use.