Most of you guys know what these sexualities are...
But! Before explaining what these are, let me tell some basics.

This picture clearly explains the difference between gender and sexuality.

Anyways,I'll tell you the meaning of the sexualities mentioned above:-
1) Homosexual- Sexually attracted to the same gender
2) Heterosexual- Sexually attracted to the opposite gender
3) Bisexual- Sexually attracted to both genders male and female.
4) Pansexual - Sexually attracted to people with a nice personality regardless of their gender
5) Demisexual - Sexually attracted to only those with whom they have an emotional connection with.

Transgender is a gender, not a sexuality.
We will talk about them in the upcoming chapters.