Sexual orientation in which one is attracted to, both emotionally, sexually, and/or visually, to any gender.
To be open about what will attract one to another. A form of sexuality, where the criteria is more about the person, not their gender or the influence of society norms.
To be attracted, in an emotional sense can be pansexual. It does not require actual sexual relations, though it can.
Pansexual is wider in scope, as it encompasses all variations of sexual orientation, which Bisexuality does not. Pansexuals will not rule out sex or attraction to such other groups such as, transgenders, transsexuals.
Another term that could be applied equally with 'pansexual' is 'omnisexual'.
Use of this term is more about the person being attracted to an individual, not a group or gender. In the meaning, it does not mean that having an attraction for a person of the same sex, means that they are attracted to all members of that gender, simply that one who exhibits traits preferred by the other.
Nor does being Pansexual mean that all twinks would be attractive to another male who likes a younger man. It simply refers to one's ability to freely engage in feelings, and sex if available, with another person.
Noteworthy: Those who refer to themselves in this manner, do so as sort of a statement, that people are not able to be sexually classified to being involved in just two sexes, that being heterosexual and homosexual. Nor does it acknowledge that they are limited to three, with bisexuality being the third.