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Cryptography is the study of ways to convert information from its normal, comprehensible form into an obscured guise, unreadable without special knowledge — the practice of encryption. In the past, cryptography helped ensure secrecy in important communications, such as those of spies, military leaders, and diplomats. In recent decades, the field of cryptography has expanded its remit. Examples include schemes like digital signatures and digital cash, digital rights management for intellectual property protection, and securing electronic commerce. Cryptography is now often built into the infrastructure for computing and telecommunications; users may not even be aware of its presence.