With the usual conversation mode of Gmail, the messages with identical subject lines are hidden under the most recent message and are considered as the same conversation. You need to click it to see the rest. This conversations view is an important feature liked by many users.
But there are some people who does not like the conversation view. They want to see each email as separate entry and want to have the new emails listed as independent unread messages on the top of the inbox email list. Respecting their requirements, Google has recently introduced a new feature settings in Gmail which will help the users to turn off the conversation view.
Switch off threaded conversations
In order to switch of the conversation view, Go to Settings -> General -> Conversation View and switch conversations on and off.
Google Apps administrators will need to activate the “Enable pre-release features” option in the Google Apps control panel to allow users to switch between conversations and an unthreaded view (more on how to do that later in the story).