Click on the down arrow 
next to Source to reveal the menu.
Select one of the following options:
| Live Session: |
Run a live session on a client. (Default) |
| Session Replay: |
Playback a previously recorded session |
| Simulation: |
Simulates a live session, useful for testing and training purposes. |
visit the topic on the basic controls in cygnet for a video on selecting the source
