Question

Aren’t check (tick) buttons more useful?

Why do they exist?

They seem quite unnecessary to me, can you please explain to me the purpose of radio buttons?

Answer 1

They are used so that only one option can be chosen out of a group of options. Check buttons allow the user to choose multiple options.

Edit:

If the goal is to have check boxes for which only 0 or 1 of the boxes in a group is checked, then check out the jsFiddle from this answer. It presents a simple way to do this using jQuery.

Here’s the Javascript code used:

$("input:checkbox").click(function() {
    if ($(this).attr("checked") === true) {
        var group = "input:checkbox[name='" + $(this).attr("name") + "']";
        $(group).attr("checked", false);
        $(this).attr("checked", true);
    } else {
        $(this).attr("checked", false);
    }
});