A serial interface is a method of communication that transmits data one bit at a time over a single channel or wire. This type of interface is commonly used in devices like computers and peripherals, allowing them to exchange information efficiently. Examples of serial interfaces include RS-232, USB, and I2C. Serial interfaces are often preferred for long-distance communication because they require fewer wires compared to parallel interfaces, which send multiple bits simultaneously. This simplicity reduces the chances of interference and makes it easier to connect devices. Additionally, serial communication can be faster and more reliable in many applications.