EXTERNAL SPEAKER / COMPUTER PLAYBACK - Playback your recordings on the external speaker. Remove the SD card and playback/store the recordings on any MAC or Windows computer; no extra software is needed. VOICE/MEETING RECORDER MODE - Functions as a regular voice recorder for recording meetings/lectures. CALLER ID / ASSISTANT RG SOFTWARE - Displays the callers information on the LCD screen (must have caller ID enabled phone line). Stay organize with the Call Assistant software (windows users only); easily manage and organize all your recordings.