What's the difference between "junk" and "trash?"

"junk" = "spam". Most people use them as synonyms in the context of email messages.

Mac's Mail.app has only the "junk" folder. Other programs or webmail may call it "spam".

Mail's Trash contains messages that you deliberately discard. Mail will not move junk email to the Trash automatically, unless you configure it so.

I’m having an issue with gmail on my iPhone 7. Emails are automatically going to a “trash” folder without me ever seeing them. How do I stop or manage what goes in there?

Timothy Arends1 wrote:

In Mail, in the Mailboxes pane, there are both "junk" and "trash" mailboxes.

What is the difference between these? I thought they were both synonyms for the same thing.

In addition, I don't see a "spam" mailbox in Mail. Is that different from "junk" and "trash"?

This is important, because when I sign up for a forum, it will tell me I must check for a confirmation message, and if I don't see it, I must check my "spam," "junk" or "trash" folder.

Which folder am I supposed to check?

I don't see the confirmation in either "junk" or "trash," so does that mean it's in the missing "spam" folder???

Junk = Spam

Trash = what you have deleted

Pete

so if i put an email in junk, that sender will be considered spam and i will never receive an email from them again?