mouse droppings
1. <graphics, operating system, jargon> Pixels (usually single) that are not properly restored when the mouse pointer moves away from a particular location on the screen, producing the appearance that the mouse pointer has left droppings behind. The major causes for this problem are MS-DOS programs that write to the screen memory corresponding to the mouse pointer's current location without hiding the mouse pointer first, and mouse drivers that do not quite support the graphics mode in use.
2. <web, jargon> The client address recorded in a web server's log whenever a client connects to a site.
Users may be unaware that their activity is being logged in this way but the potential for misuse of the information is limited.
[March 1996 Macworld, p260, Viewpoint article by Larry Irving].