What is the purpose of the HTML “no-js” class?

Question

I notice that in a lot of template engines, in the HTML5 Boilerplate, in various frameworks and in plain php sites there is the no-js class added onto the

Answer 1

This is not only applicable in Modernizer. I see some site implement like below to check whether it has javascript support or not.

    
    ...

If javascript support is there, then it will remove no-js class. Otherwise no-js will remain in the body tag. Then they control the styles in the css when no javascript support.

.no-js .some-class-name {

}