tags in web.xml

I Like to know what is the use of following tag in the wb.xml. Yes i understand it will say our project name, is there any thing more here. I also like to know is there any link which will info about all the tags in web.xml.

<display-name>SSP Global</display-name>
<description>SSP Global Application.</description>

Basically,
The web.xml is used for creating some webapplication, as you have created for your project.
The root element for all this web.xml is <webapp> , i think as you know it already, and all the other filed inside this are optional one.
basically, you need a server this may be weblogic , or tomcat to run this application.
so,
The display name as you have mentioned is the web-application display name, for your project you give your project name, for some x application you give that x name and so, on,
and , the next field you give the description of your particular application, as for your project you give the description of your project and so on.

but, basically the weblogic does not handle this currently, may be due to some reasons.