Private Channel Recordings
Playback is only available to members of a the private channel. Only members of said channel have access to these type of recordings, not the entire team. A member of a private channel does not need to participate in a conversation in order to have access to it.
Private Personal Recordings
All one to one calls produce a recording. If the call was selected to be private (at the origination or during a call) then the recording will only be available to its participants and no one else.
Public Channel Recording
Playback is available to all on your team. These recordings are typically a result of a watercooler conversation that was not made private or a conversation that took place in a public channel.