If you want to write more information about an object or want to bring this to the attention of your colleague(s), you can post a message. You can do this by first selecting a specific object, then clicking the "Messages" tab. You will now see the screen below.
If you want to bring the message under the attention of other users, select “mention user”. By selecting the name from the dropdown box the selected user will see the message on his dashboard.
If you only want to place the comment, you only have to click on “Post message”. After which you don’t need to save the object.