Delete moves an email to Trash so you can restore it before permanent deletion. Archive moves it out of your everyday mail views without scheduling deletion. A rule's Auto-delete action is different: it schedules permanent deletion and skips Trash.
Trash
Deleting from the reading view, bulk action bar, or a row swipe moves the email to Trash. A rule that sets Deleted status does the same. The list shows trashed mail from every inbox, newest first.
Trash normally keeps an email for 30 days before permanent deletion. If your rules also set an Auto-delete duration, that schedule takes precedence and counts from the original receipt time. See Auto-delete rules.
Discarding a draft deletes it permanently on the spot. The 30-day window applies to received and sent mail, not drafts.
Restoring an email
Select rows and choose Restore from the bulk action bar, use the restore button that appears when you hover a row, or open the email and choose Restore. The email returns to your mail views marked as read (sent mail returns to Sent), keeps its category and inbox, and the 30-day clock is cancelled.
Delete forever
Delete forever removes an email immediately, without waiting out the 30 days. It's available on a row, in the reading view, or in the bulk action bar for a selection. This one is irreversible, so it asks for confirmation. Everything the email carried, including attachments, is removed.
Archive
Archived mail leaves Everything, category views, and inbox views. Search still finds it and marks the result Archived. You can archive mail from the reading view, bulk action bar, or a row swipe. Rules can also set Archived status, and a move to an Archive folder in a connected IMAP client archives mail. Find archived mail under Archive in the sidebar.
Archiving doesn't itself schedule deletion. However, rules can combine Archived status with Auto-delete, so an email archived by rules can still be scheduled for permanent deletion.
Unarchiving
Select rows and choose Unarchive from the bulk action bar, use the hover button on a row, or open the email and choose Unarchive. The email returns to your mail views marked as read. Deleting from the Archive view moves mail to the trash, where the normal 30-day window applies.
If a rule keeps archiving mail you want to see, open the email's inbox settings and adjust the rule. Reprocess isn't available in Archive or Trash. Unarchive or restore received mail before applying your current rules to it.