when to use checkbox and radio buttons code example

Example 1: checkbox as radio button

input[type=checkbox]:not(old) + label,
input[type=radio   ]:not(old) + label{
  display      : inline-block;
  margin-left  : -2em;
  line-height  : 4em;
}

Example 2: composition with checkboxes and radio buttons

Radio[] buttons = new Radio[2];