If you're a developer looking to supplement your own data tools and services, this concise ebook covers the most useful sources of public data available today. You'll find useful information on APIs that offer broad coverage, tie their data to the outside world, and are either accessible online or feature downloadable bulk data. You'll also find code and helpful links.This guide organizes APIs by the subjects they coversuch as websites, people, or placesso you can quickly locate the best resources for augmenting the data you handle in your own service. Categories include:Website tools such as WHOIS, bit.ly, and CompeteServices that use email addresses as search terms, including GithubFinding information from just a name, with APIs such as WhitePagesServices, such as Klout, for locating people with Facebook and Twitter accountsSearch APIs, including BOSS and WikipediaGeographical data sources, including SimpleGeo and U.S. CensusCompany information APIs, such as CrunchBase and ZoomInfoAPIs that list IP addresses, such as MaxMindServices that list books, films, music, and products