There are four different types of email bounces: hard, soft, spam and other.
A hard bounce means that the recipient’s email address does not exist or is permanently undeliverable. You will not be able to send again to email addresses who have hard bounced.
Soft bounces are temporary bounces, like those caused by a full inbox.
Spam is when the recipient’s spam filter thinks the message is spam and therefore the message isn’t delivered to the recipient's inbox.
Bounces that Lime Marketing cannot interpret because the bounce code and text the system receives are non-standard end up under other bounces.