What is typeahead.js?

Typeahead.js is a JavaScript library for building autocomplete (also called typeahead) inputs, the kind where suggestions appear below a text field as you type. It was created by Twitter, inspired by the autocomplete search box on twitter.com. The library has two separate parts that work together. The first is Bloodhound, the suggestion engine, the behind-the-scenes logic that figures out what suggestions to show based on what the user has typed. It can fetch suggestions from a remote source or use a pre-loaded local dataset. The second part is the Typeahead UI view, which handles rendering the dropdown list of suggestions and responding to user interactions like clicking a suggestion or pressing the arrow keys. Both parts can be used independently if you only need one piece, but together they give you a complete, polished autocomplete experience. The library depends on jQuery (version 1.9 or later), so it is designed for projects that already use jQuery. You add it to your page by including one of several downloadable bundles: a combined bundle with both components, or the two parts separately. You would reach for typeahead.js when you want to add an autocomplete feature to a search box or form field on a web page and want more control and flexibility than browser-native autocomplete provides. It supports the major desktop browsers including Chrome, Firefox, Safari, Internet Explorer, and Opera. Note that the library is not tested on mobile browsers.