How to pronounce /p/ and /b/

The 'p sound' /p/ is unvoiced (the vocal cords do not vibrate while producing it), and is the counterpart to the voiced 'b sound' /b/.

   To create the /p/, air is briefly prevented from leaving the vocal tract by closing the lips. The sound is aspirated when the air is released. The aspiration for a /p/ is greater than the aspiration for a /b/.