Google Programmable Search Engine (formerly known as Google Custom Search and Google Co-op) is a platform provided by Google that allows web developers to feature specialized information in web searches, refine and categorize queries and create customized search engines,[2] based on Google Search. The service allows users to narrow the 11.5 billion indexed webpages down to a topical group of pages relevant to the creator's needs.[3] Google launched the service on October 23, 2006.[4]