This knol written by gravi_t, an active member of the Gmail group, does a good job at explaining the features that make Gmail different.
Imagine this:
- each email is a piece of paper
- labels are post-it notes, sticky notes
- there are default labels, like "Inbox", "Sent items", "Trash" ("Bin"), "Spam"
- you can also create labels (i.e. sticky notes)
This means that - unlike in other email services - you do not put the emails into folders. You actually attach labels to the emails.
Only one copy of your emails:
- you only just have ONE existing copy of your emails
- no matter how many labels (post-its) you stick on them
- you can attach as many labels to this one copy as you want, just as you can stick a lot of post-it notes to the same one piece of paper
This is why your email disappears from everywhere when you delete it; because deleting the email means deleting the "piece of paper"!!
The knol is licensed as Creative Commons Attribution-Noncommercial and Google should use some of its content in the "welcome" message.
Tip: To find when you created a Gmail account, go to "All mail", click on "Oldest" and you'll see the first messages you've received. You'll need this information to get access to a compromised Gmail account.
{ Thanks, Anonymous. }