XSS attacks are becoming a big problem and are going to become an extremely big problem if people do not educate themselves about XSS attacks and vulnerabilities. XSS vulnerabilities have been found in all sorts of websites including fbi.gov, yahoo.com, ebay.com and many other popular and important websites, a lot of administrators fail to pay attention to XSS attacks because they either don't know much about them or they do not see them as a threat. An XSS vulnerability when exploited by a skilled attacker or even a novice can be a very powerful attack. This paper details XSS attacks and hopes to educate you on what they are, how attackers use them and of course how you can prevent them from happening.