Simple. Search box, whether website or address book, when typed it either jumps to or filters results. Commonly uses autocomplete. NOT the same as location jump at all. This is ONLY applied when already within the results, like a page or infinite list. Not used to search the internet, etc.
ALSO the widget to type a name in an address book, and it jumps to the first location with it (or where it would be, unlike Search Within, never a "no results" state). See search-within for a contrasting widget -- discuss that strictly it's a Location Within, since there are always results, and it just jumps but since there is typing the interaction model is more akin to this pattern.
Problem
Solution
Variations
Interaction Details
Presentation Details
Antipatterns