One of two types of ports on a personal computer to which peripheral devices can be connected. In contrast to a parallel port, a serial port transmits data in a linear fashion, one bit at a time, rather than as a larger collection of bits. Printers, for example, are commonly connected to Macintoshes by means of a serial connector. Mice and other input devices are also connected to both Macs and PCs by means of a serial connector. See also Parallel Port.