<input type="checkbox" checked>
enables you set iniatially checked
use
http://www.w3schools.com/html/html_forms.asp
for more example about DOM structure and html elements.
if it is not the case make a clear definition of your problem or provide sample code to be observed.
Good luck.
:)
no... if you are using html:checkbox, then it's going to base the checked state of the box automatically for you based on the value of the property of the form bean for the form. If the value of the form bean's field for that checkbox property matches the value of the html:checkbox tag you define, it'll check it, else it won't.