Why doesn't list-style:none work in CSS?

Code See below? Why does List-style:none not work?

<! DOCTYPE HTML PUBLIC "-//W3C//DTD XHTML 1.0 transitional//en" "Http://www.w3.org/TR/xhtml1/DTD/xhtml1-transitional.dtd ">
No UL default rating is high.

Why should I set it on the body?

You set the body above, then the UL is to inherit the body's settings, inherited things, will be carried by the properties of their own covered.

A very complicated question
Can you understand this:
The default style of UL belongs to the inline style sheet
The body{in the head tag ...}, which belongs to the internal style sheet
Internal style sheets are less prioritized than inline style sheets

If it doesn't, it's best to add it to the CSS style in the Div, which is the most stable.

Written on the body in theory can be inherited by the body inside the element, but the permissions inherited in the CSS is the lowest, so it will be UL's own default style coverage, such code is generally directly addressed to the UL

ul{        list-style:none;    }