Originally published at: http://www.sitepoint.com/building-simple-rest-api-mobile-applications/
Representational State Transfer (REST) is lightweight, HTTP based and runs on web servers much like ‘normal’ web sites. Instead of delivering in HTML, which is a combination of presentation and data, data is displayed with minimum formatting using separators and delimiters (like JSON). It can be thought of as an architectural style for designing networked applications or as a way of delivering web services. REST is browsable, so helps developers modify and check the correctness of their code as only the data is displayed in the browser. It is a safer method of providing services or data access as it does not expose much unnecessary surface area of the database used by the website. Some well-known REST apis are from Twitter and Facebook Graph.
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