Embodiments provide a system, method, apparatus, means, and computer program code that allow multiple annotations to a document to be created and that distinguish between the annotations made by different people. The people may view documents, exchange ideas and messages, etc. via a server or conference/collaboration system at different times and/or without being in direct communication with each other. In such an off-line collaboration mode, the people may want to add listen to, view, or add annotations regarding one or more documents. The methods and systems described herein allow users to follow the trail of annotations regarding a document and to distinguish between the voice or other audible annotations created by other people.