How do mail servers work?
How do mail servers know where to send your mail?
Mail servers are often described as electronic post offices. They receive, sort and deliver your email and attachments to the address the sender specifies.
Each and every hosting provider and ISP(Internet Service Provider) will be running a mail server program on each of their servers. As soon as you click “Send” on your completed email. Your hosting provider (or ISP depending on your outgoing server settings) will receive your email request.