What is the difference between someone who identifies as pansexual and someone who identifies as bisexual?

The main difference between identifying as bisexual and pansexual is that a bisexual person can feel attraction towards two (bi) categories: men and women. People who identify as pansexual can feel attraction for people of all (pan) gender identities, including people who identify as men, women, gender non-conforming, transgender, genderqueer, non-binary and other gender identities.