Email delivery refers to the process of sending an email from one user to another through the internet. When you hit "send," your email client communicates with a server, which then routes the message to the recipient's email server. This involves various protocols, such as SMTP (Simple Mail Transfer Protocol), to ensure the email reaches its destination. Once the email arrives at the recipient's server, it is stored until the recipient checks their inbox. Factors like spam filters, server issues, and incorrect addresses can affect whether the email is successfully delivered. Proper email delivery ensures that messages are received promptly and reliably.