There's a lot of groups so it'd be a bit difficult to name them all without getting anything wrong.
The most well-known ones are probably Gay, Bisexual, Pansexual, Asexual, and Lesbian.
The best way to not offend someone is by asking them before anything. And if you don't know what that sexualities 'means' than just ask. Most people will be happy to tell and share with you what they are.

Yeah, that makes sense. Thanks for the help!!!!

No problem! If you have any more questions I'll be happy to try and answer them ^-^

Thanks again! You've been a huge help and probably saved me from accidentally offending people in the future! ;)

User: Hiraeth
Pronouns: irl female, but whatever boats your float.
LGBTQ+-ness: very bi
Pinglist: sure
Hex: C363FF
Things to say: It's unhealthy to feed ducks a lot bread. :(

Welcome into the club!
And the things to say is something I never knew surprisingly.

Thank you! I like ducks. I used to work at a place that had them over the summer, and the more you know about ducks...

Username: CloudedOtter
Pronouns: They/them
In what way are you a part of the LGBTQ+ community: Brainstuff makes all of this more complicated. I usually stick with trans, aro/ace-spec, and Q (can't put the whole word because it gets censored)
Pinglist: Nah
Color hex (0000FF is an example): #e3b707
Any other thing you'd wish to say: I'm not sure how active I'll be since I tend to feel out-of-place in spaces where everyone is younger than me. That being said, I've been lurking and reading the conversations for a while, so I might as well make myself known.

Welcome in! ^-^
And it's alright if you don't feel comfortable talking or just don't want you (:

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