CORS

Cross-Origin Resource Sharing - CORS - is a mechanism for allowing restricted resources (CSS stylesheets, images, and scripts) to be accessed across domains even when they originate inside scripts.

This mechanism gives web servers cross-domain access controls, which enable secure cross-domain data transfers.

Modern browsers use CORS in an API container - such as XMLHttpRequest or Fetch - to mitigate risks of cross-origin HTTP requests.

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