A technology invented by Microsoft that essentially entails the software trying to sense a user's intentions and react to them.

Intellisense is actually a fairly general term, which refers to a slew of features--for example, in Internet Explorer 5.0, it refers to the browser's auto-completion of typed URLs and auto-correction of typos in URLs.

The term is probably best known as the feature of the Visual Studio products which displays symbol information as one writes code; for instance, when writing a function call, the entire function's parameter list will be displayed in a tool tip, with selectable constants in comboboxes.

Ironically, Microsoft's Intellisense is missing one of the world's earliest (and best) Intellisense technologies: tab completion.