Question

Suppose this checkbox snippet:

<input type="checkbox" value="1">Is it worth?</input>

Is there any reason to statically define the value attribute of checkboxes in HTML? What does it mean?

Answer 1

I hope I understand your question right.

The value attribute defines a value which is sent by a POST request (i.e. You have an HTML form submitted to a server).
Now the server gets the name (if defined) and the value.

<form method="post" action="urlofserver">
    <input type="checkbox" name="mycheckbox" value="1">Is it worth?</input>
</form>

The server would receive mycheckbox with the value of 1.

in PHP, this POST variable is stored in an array as $_POST['mycheckbox'] which contains 1.