LapLink, from Traveling Software Inc., enables users to easily and quickly move files between two DOS computers using only a serial null-modem cable or a special parallel port connector. No other hardware is needed. Laplink was extremely popular.during the late 80s and early 90s. It was infinitely easier to set up any two arbitrary PCs (often portables or laptops) with LapLink than other methods, such as DOS based networking. MS-DOS 6 bundled a similar set of file transfer tools called INTERLNK and INTERSVR.