A parallel port is a type of interface used to connect devices like printers and scanners to a computer. It allows multiple bits of data to be transmitted simultaneously, making it faster than serial ports, which send data one bit at a time. Parallel ports typically use a 25-pin connector and were commonly found on older computers. Although parallel ports were widely used in the past, their popularity has declined with the advent of newer technologies like USB and wireless connections. Today, most modern devices do not include parallel ports, as they have been largely replaced by these more efficient and versatile options.