This can be difficult and people may worry that others will treat them differently once they know.
Even though it can be scary, most people feel that coming out is important as it means they can be honest about how they feel and not keep an important part of their life hidden.
Getting to know yourself and your sexuality
One of the first steps of coming out is acknowledging to yourself what your sexual preference is.
For many people, admitting to themselves that they're gay, bisexual or lesbian can be hard for many reasons.
It could be because they have been brought up to think being gay is wrong, or because they are worried about being teased or bullied.
If you're not sure if you're gay, lesbian or bisexual, you may find it helpful to talk to someone you trust about your feelings.
Who to tell about your sexuality
When you first come out, the most sensible option is to tell someone who you trust, and who will be supportive and understanding.
It will help if they can keep a secret, as you may not want other people finding out before you feel comfortable about your sexuality.
This person could be a close friend or relative, or, if you're younger, it could be a trusted adult, such as a teacher or youth worker.
Will coming out change things?
Hopefully, coming out will change your life for the better, as you won't feel there's a big part of you that people don't know about. Many people say they feel relieved they can be open about how they feel.
However, there can be a downside to coming out. You may come across people, including friends and family, who are homophobic (prejudiced against gay, lesbian and bisexual people). They may make you feel angry, upset or scared. You may experience discrimination.
This is why it can be helpful to tell a small group of trusted people first. That way, you'll feel supported and have people to talk to about the reactions you may face.
When is best to come out?
If you're not sure how you feel about your sexuality, there's no hurry to make your mind up or tell people.
Coming out is an individual decision, and it's important to do it in your own way and in your own time.
Article provided by NHS Choices