<action path="/sample" forward="/example" />

Help me to know why the highlighted '/' are used @ the starting of the code itself

I'm not sure what you're asking. The "/sample" is the text value inside the 'path' attribute. It has nothing to do with the @ symbol at all.

/action/@path

This returns a text value of "/sample" The '/' is just part of the string, it could be anything inside that attribute value. Is there some kind of problem you're having based on this data?

<html:form action="/some-action.do" >

i am asking about why the '/' back slash is used in code in that particular location.

thank u

but still let me know some detailed information on that.