Junk email messages claiming that you have won a "lotto" or a "lottery" are common right now because people respond to these emails. That tells the junk emailer that there is a real person at the email address. Then they sell your address to unscrupulous companies, and you get more junk email.
Some online criminals will also attempt to find out more information from you, such as your bank account information, or ask you to pay a fee for the delivery of the lottery money. There is no lottery, you did not win anything, do not respond.
If you have entered a legitimate contest on a website belonging to a legitimate company, things might be different. But large lottery prizes are not awarded by email alone because it is much too unreliable. Also, watch out for phishing scams, emails falsely claiming to be from legitimate companies. These may contain many legitimate links to the "real" company, but the one they are counting on you to follow will go somewhere else. Check the address bar at the top of your browser before believing that you really are on the site an email message claims to link to.
Some of these emails claim to be sponsored by "World Wide Web." There is no such company or organization. The term World Wide Web doesn't refer to a particular company, so it can't sponsor anything. The W3C Consortium, which sets standards for the Web, is not in the lottery business.
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