Gmail folders in your mail client
The [Gmail] subfolders represent the special labels visible in the Gmail web interface: All Mail, Drafts, Sent Mail, Spam, Starred and Trash.
[Gmail]/All Mail contains all of your messages in Gmail, including your sent and archived messages. Any messages that you see in your inbox will also appear in the [Gmail]/All Mail folder.
If you save any drafts in the web interface, they can be found in the [Gmail]/Drafts folder. We recommend that you set this folder as the drafts folder for your email client, so that any drafts you save in your client will be waiting for you in the web interface as well.
Moving a message to [Gmail]/Trash in your email client will move the message to Trash in the web interface and will mark the message for permanent deletion. Moving a message to [Gmail]/Spam will report the message to Gmail as spam and will also mark the message for permanent deletion. We strongly recommend that you do not set either of these folders as the trash folder for your email client.
Please note that you cannot remove the [Gmail] subfolders from your email client.