7a8f0515_Stock_Photo_API___Shutterstock__Description
[Code] 401 [Name] Unauthenticated [Description] 
This code is officially named "Unauthorized," but what it really means is "Unauthenticated." This means that you have not identified your client to the API. You must provide your API credentials in your Authorization header or using the cookie from a previous recently-authenticated response. For more information on the concept of "authorization," ccessing the API (in its proper sense, that is, the decision of whether to allow access by an authenticated user to a given resource) as well as the concept of authenticating as a specific Shutterstock customer or submitter (not just a general API client), see status 403 below.
Stock Photo API - Shutterstock
Description