The article explores how the X.400 email standard, developed in 1984, included many advanced email features such as message recall, scheduling, encryption, and multilingual support long before SMTP-based internet email adopted them. However, due to its complex, top-down design and difficult implementation, X.400 failed to achieve widespread interoperability and usability, allowing the simpler, more adaptable SMTP protocol to become the foundation of modern email despite lacking some of X.400’s richer features.
Email Could Have Been X.400 Times Better
