When to use “!important” to save the day (when working with CSS)

Question

#div p {
    color: red !important;
}
...
#div p {
    color: blue;
}

I understand how !important works, in this case the div will ren

Answer 1

If your page includes multiple CSS files, the CSS written by you, and additional CSS that go with software written by other parties, you may want some of your CSS marked !important to "guarantee" it will not be overridden by CSS from other included files.