Typeahead.js is a fast, fully-featured jQuery autocomplete library inspired by twitter.com autocomplete search functionality.
Typeahead.js can displays suggestions to end-users as they type, Shows top suggestion as a hint (i.e. background text) and allows suggestion to be drawn from multiple datasets.
The Library also works with hardcoded data as well as remote data, rate-limits networks requests to reduce server load. It supports customized templates for suggestions and plays nicely with RTL languages and input method editors.