Browsers using Backspace keypress to navigate Back is evil, especially for large forms. On a jQuery-enabled page, this will capture Backspace and discard it unless a form field is in focus.

capture-backspace.js

$(function() {

    var tagRegex = /INPUT|SELECT|TEXTAREA/i;
    var typeRegex = /DATE|DATETIME|DATETIME-LOCAL|EMAIL|MONTH|NUMBER|RANGE|SEARCH|TEL|TEXT|TIME|URL|WEEK/i;

    $(document).on('keydown keypress', function(e) {

        if (e.keyCode == 8) // Backspace
        {
            if ( !tagRegex.test(e.target.tagName) || e.target.tagName.toLowerCase() == 'input' && !typeRegex.test(e.target.type) )
            {
                e.preventDefault();
                console.info('Prevented backspace key from navigating back.  Tag: ' + e.target.tagName.toLowerCase() + ', ID: ' + (e.target.id || '(none)') + ', Type: ' + (e.target.type || '(none)'));
            }
        }
    });
});