What are my audio devices?

Run the command (in the terminal)

aplay -l

The output looks like

**** List of PLAYBACK Hardware Devices ****
card 0: Intel [HDA Intel], device 0: ALC262 Analog [ALC262 Analog]
  Subdevices: 1/1
  Subdevice #0: subdevice #0

The device for this is plughw:0,0. The two zeros come from the device 0 and Subdevice #0.