Mozilla defines a special JavaScript object to allow web pages access to certain cryptographic-related services. These services are a balance between the functionality web pages need and the requirement to protect users from malicious web sites. Most of these services are available via the DOM window object as window.crypto.
This specification describes a JavaScript API for performing basic cryptographic operations in web applications, such as hashing, signature generation and verification, and encryption and decryption. Additionally, it describes an API for applications to generate and/or manage the keying material necessary to perform these operations. Uses for this API range from user or service authentication, document or code signing, and the confidentiality and integrity of communications.