As one of the members said PHP is cheap for hosting and fast.Also PHP is easy to learn and apply.For JSP easy hosting is not available also it is costly.Same with ASP.But quality wise JSP is good.Also for security JSP is good.
JSP is also good but when it comes to hosting, PHP is cheap and more popular that JSP. And if you are serious into web development, JSP is better because you can easily incorporate the other java technology like J2EE and javabeans.