The set of technologies, systems, and protocols used to manage, send, receive, and process email communications. This infrastructure includes various components such as email servers, email clients, and communication protocols like SMTP (Simple Mail Transfer Protocol), IMAP (Internet Message Access Protocol), and POP (Post Office Protocol). Email infrastructure supports the entire lifecycle of an email, from creation and sending to delivery and storage. It ensures that emails are transmitted securely, efficiently, and reliably across networks. Key aspects include server management, email authentication (like DKIM, SPF, and DMARC), deliverability optimization, and data storage. Effective email infrastructure is essential for maintaining performance, security, and scalability in email operations, whether for personal use or large-scale business communications.