What is SMTP (Simple Mail Transfer Protocol) and how does it work?

SMTP (Simple Mail Transfer Protocol) is a communication protocol used for sending email messages between servers. It is the standard method used for email transmissions over the internet.

SMTP works by initiating a connection between the sender's email server and the recipient's email server. The sender's server sends the email message to the recipient's server, which then delivers it to the recipient's inbox.

SMTP uses a series of commands and responses to facilitate the transfer of email messages. It operates on port 25 by default, but can also use other ports for secure connections.

Overall, SMTP plays a crucial role in the transmission of email messages and makes it possible for individuals and businesses to send and receive emails reliably.