How Email Delivery Works: From DNS and MX Records to the Inbox When you send an email, it looks simple: you write a message, click Send, and it appears in the recipient's inbox. But behind that simple action, several systems work together. If you're building a web application that sends or receives email, understanding this flow is extremely useful. While building InboxOro, I spent a lot of time working with email infrastructure, DNS, SMTP, and message processing. In this post, I'll...