This term means the whole process of connecting to a computer over a telephone link. For example, if your main computer is at the office, but you decide to work from home, you can dial-up the office computer and access all the files stored on it or even log on to the office network and send messages - just as if you were there. To do this you need two modems, one on each PC, and the dial-up software that's supplied with Windows 95 (install the dial-up networking option of Windows to use this feature).