Sexuality can mean different things to different people. It is all about our sexual preferences - that means who we fancy.
Some people know from a very young age whether they fancy girls, boys or both. But for some other people it can take time to work out how they feel. The most important thing to remember is that it is normal for us to take time to work out who we are, and no-one should pressure us to feel one way or another.
It is a totally personal thing!
Click here to read more about what it means to be gay, bisexual, heterosexual or asexual.
It can be daunting for some people when they realise that they fancy people of the same sex,
and want to tell their friends and family about it. How will they react? What will they say? Will they look at me in the same way after I tell them? These are all questions that might pop into a person's mind when they imagine having that conversation.
But talking about the way you feel with people you trust is an important part of embracing who you are - and can be a very positive and supportive experience.
A good starting point is telling someone who is very likely to be supportive and helpful. This can help with gaining the confidence to tell other people - and it means that person is there to help, whatever happens next.