move_attachment_column

By default  in Gmail  icon column of all items in your inbox will appear on right of the screen with which we can able to distinguish various items  like messages with attachments,calendar invitations, Buzz posts , chats.Move Icon column labs feature for Gmail will bring this icon column to the left side of screen.

move_icon_column

These icons visible prominently at left side of screen in Gmail.So enabling Move Icon Column labs  feature will improve visibility of the icons .

enable move icon colomn

To enable move Icon Column labs feature  in Gmail , in Gmail click Settings >Labs scroll down to Move Icon Column Label entry  and enable it.