A RESTful web API (also called a RESTful web service) is a web API implemented using HTTP and REST principles. It is a collection of resources
Link: http://en.wikipedia.org/wiki/Representational_state_transfer
Sometimes an organization may seem like a small difference between the REST API and Restful web services. For example, the Rest API can be shared by everyone to use data with the same endpoint.
Soothing web services may come with custom modifications for a specific requirement, and the endpoint will be different.
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