Encrypted Media Extensions provides an API that enables Web Applications to Interact with content protection Systems and play Encrypted Audio and Video Data.
EME was developed to enable the use of the same App and Encrypted files in every browser, regardless of the underlying protection system. The former is made possible by the standardized APIs and data flow, while the latter is made possible by the concept of shared encryption.
EME is an extension of the HTMLMediaElement specification – hence the name. An “extension” means that browser support is optional for EME: if a browser does not support encrypted media, it cannot play encrypted media, but EME is not required to comply with HTML specifications.