DisplayPort is the first display interface to rely on packetized data transmission, a form of digital communication found in technologies such as Ethernet, USB, and PCI Express. It permits the use of internal and external display connections, and unlike legacy standards that transmit a clock signal with each output, the DisplayPort protocol is based on small data packets known as "micro packets", which can embed the clock signal within the data stream. This allows for higher resolution using fewer pins. The use of data packets also makes DisplayPort extensible, meaning additional features can be added over time without significant changes to the physical interface.