html input label

1<!-- By reference -->
2<label for="first_name">First Name</label>
3<input type="text" id="first_name" name="first_name">
4
5<!-- By wrapping -->
6<label>First Name
7  <input type="text" name="first_name">
8</label>

1<label for="id_of_what_you're_labeling"></label>
2
3<!-- for example-->
4<label for="username"></label>
5<input type="text" id="username">