an automatic message that will go out to your users when they sign up for your newsletter through your Opt In Form on your website
an autoresponder - a message that's sent to new names when they are added to a list
an email sent to all new users who subscribe to your list, and a Goodbye message is an email sent to all users who unsubscribe from your list
The message that the Immigration Officer says to the people who enter the world
Message sent automatically to new list members as soon as their email addresses are added successfully.
A message sent to new subscribers to an email list, usually sent automatically by the list server.