The AS-8144B is a Bitronics Auto Switch that will operate in either, one computer to four printers mode, or four computers to one printer mode, called respectively 1 to 4 mode and 4 to 1 mode. These switches operate in 4 to 1 mode without software drivers and deliver print jobs to the printer on a first come, first served basis. This means that if one computer is printing to the printer the other three computers must wait for the Auto Switch to finish the current print job. The AS-8144B, when operating in 1 to 4 mode, users the AS Ware driver to select which printer of the four attached to the Auto Switch will print the print job. You can only be printing to one printer at a time unless all four printers are identical and you wish to rapidly product many copies of the same document. The AS-8144B can go into a unique "broadcast" mode and all four printers will print the exact same document, leaving you with four copies.