Parallel port printer port or Centronics port found on most personal computers from the 1970s through the 2000s. It was an industry "de facto" standard for many years, and was finally standardized as IEEE 1284 in the late 1990s, which defined the Enhanced Parallel Port (EPP) and Extended Capability Port (ECP) bi-directional versions. Today, the parallel port interface is virtually non-existent because of the rise of Universal Serial Bus (USB) devices, along with network printing using Ethernet and Wi-Fi connected printers. The parallel port interface was originally known as the Parallel Printer Adapter on IBM PC-compatible computers. It was primarily designed to
Parallel manipulator mechanisms for the movement of either the robot on its base, or one or more manipulator arms. Their 'parallel' distinction, as opposed to a serial manipulator, is that the end effector (or 'hand') of this linkage (or 'arm') is directly connected to its base by a number of (usually three or six) separate and independent linkages working simultaneously. No geometrical parallelism is implied. A parallel manipulator is designed so that each chain is usually short, simple and can thus be rigid against unwanted movement, compared to a serial manipulator. Errors in one chain's positioning are averaged in conjunction with the