<INPUT TYPE="checkbox" NAME="check1" Value="Check1">Checkbox 1<BR>
The checkbox can be preseelected with the "CHECKED" attribute:
<INPUT TYPE="checkbox" NAME="check1" Value="0" CHECKED>Checkbox 1>
Or with Javascript:
form.check1.checked = true;
The checkbox can be tested to see if it is checked with Javascript:
form.check1.checked