I guess you didn’t buy any tickets in lottery? so, you are puzzled as how and why you won? its simple..scam! you were clever enough to ask before doing anything (I hope for your sake!) so, this is how they operate. There are several variations to this kind of scam. Below is some example of how they work.

1. They ask you for your personal details like; name, birthday, address, marital status and other details so, they can steal your identity.

2. They tell you that you won Million dollars/pounds and you need to send them some money to have prize processed. Amount can vary from $50 to couple of thousand dollars.

3. They ask you for large amount, usually in thousands as they have a Large cheque for you and this cheque can only be delivered by Personal courier.

4. They want you to reply to an email so, they can plan a worm virus to steal your personal details from your computer.

5. They post you a cheque for large amount, usually in thousands and you bank it. After you bank it, it usually have to sit in your account for longer than usual as it is international cheque and they reverse the cheque out of your account with any other money available or if you don’t have any money, they will deduct it from your account and leave it in minus balance.

I’m sure there are other variations but, above examples are fairly standard amongst scammers. It can be lottery, or bank manager who has client died in plane crash and no next of kin, or some rich millionaire who has met you that you don’t know about but, he has died and left you money in his will, or even poor refuge girl who’s father was banker/businessman/investor or whatever and she wants to marry you to escape refugee camp and build new life with you and usually sends you a photo of a model or someone very attractive and you need to send her money for plane ticket/medicine for her sister/pay for her education. so, you see, there is no such luck as you probably didn’t buy any ticket so, simply delete that email and I guarantee you that you will get sh!t load more email in the future. How did this happen? some one probably got hold of your email address and sold it online or they got it from online forum or even place like yahoo answers. Be careful..

Sorry friend but there is no Microsoft, Yahoo or other e-mail lottery, it’s a scam do not answer do not give personal information.The following sites give more information
http://www.snopes.com/crime/fraud/nigeri...
http://www.thescambaiter.com/forum/showt...
http://www.hoax-slayer.com/email-lottery...
.Also If you go to the following site you will get some info on ID theft http://www.identity-theft.org.uk the iinternet is safe enough if you are careful but please answer nothing that you are doubtful about.Good Luck and be careful