Seconds after I send it, my message has wormed its way to the destination server. However, the recipient will not be notified until he checks his mailbox. The type of computer used is not significant. When users, mostly companies, have a permanent connection, they are notified instantly of the arrival of new mail. On my son's Macintosh, a dog appears on the corner of the screen and barks when a new message comes in.
News groups are conferences on a variety of subjects.
This is an uncontrolled area where people will discuss anything in any language. My provider shows 15,000 different subjects. Authors of the messages are anonymous and the data may not be reliable. Pictures transmitted there range from the sublime to the nauseating. It is an interesting area to discuss medical problems, current events, gardening, anything. . .