Transgender people have a gender identity or gender expression that differs from their sex assigned at birth.
A lot of people feel that they cannot identify with the sex they're assigned at birth. This means someone assigned to be boy at birth (born with a penis) may not feel like a boy from inside. Many such people face a lot of discrimination in the society and takes a lot of preparation for them to ‘Come Out’ as Trans women or men. They can be sexually attracted to any gender.