How can I explain homosexuality to my parents?

Homosexual love is the same as heterosexual love. The only difference is that you love someone of the same sex rather than the opposite. You're attracted to people the same way you're parents are, your brain is just wired to love someone of the same sex.

at first ask if you can talk to them about a serious topic. if it is you that you want to talk about don't be afraid to tell them. make sure they know that you are not a different person

It's about the situation though depending the factors of how your parents feel about that topic. :) Try your best and know that it is okay to be scared.

Just try to do it basically, say that a female is attracted to a female and a male is attracted to another male

You can explain homosexuality to anybody, including your parents, by explaining that it's just who you are as a person. That it's just a part of you and who you are. It's how you were born and that you are only attracted to members of the same sex because of genetics; not choice.

I am a girl and I like girls. I am a boy and I like boys. You're my parents and you love me. If you can't accept my sexuality than you can't accept me. But if you're normal humane people you will understand who I am. Being gay isn't a choice. I didn't ask for this. This is who I am.

Always explain first that love is love regardless of who it is I am loving. Tell them that Being happy is worth more than being 'normal'. I love people that are the same gender as me and that is all it is.

Coming out can be really hard, for ~everyone~ involved! Parents don't always see it coming, and even if they do they might not know all the facts. Explaining homosexuality is going to best be done with facts, so I'd recommend you do quite a bit of research and have information ready and available. Parents can get upset when they find out things aren't as they imagined, and it's important to not take things personally and give them time and space to digest what is going on just like you might have needed space. Finally, it's best to hope for the best and be prepared for the worst so if in the unlikely event that they do not take the information well, remember that there are many excellent resources available to you in the LGBT community from community centers to LGBT-specializing therapists.

Well, I would try just sitting them down and having a nice, calm, serious conversation with them. Try to explain it to them gently as it can be really shocking to parents to have their child tell them something like that

It's where somebody is attracted to people of the same sex, and that it's something you're born with. It cannot be changed so all you can do is accept it and be loving to gay people! :)