Google Suggest

Overview
Google Suggest is

"an automated tool that recommends additional search queries when a user begins to type descriptive words or phrases into the search engine. These additional search queries derive from an algorithm that tracks and analyzes all queries run by internet users."

Overview
"Google Suggest lists the most popular combination of terms used by individuals conducting identical or related search queries. For example, if a user types 'chicago' into Google's search engine, even before the user presses 'enter,' Google recommends several searches: 'chicago tribune,' 'chicago bears,' 'chicago weather,' and 'chicago sun times.'