Example of bind usage

gistfile1.js

var obj = {
    clickHandler: function() {
        console.log(this); // "el"
    }
};

el.addEventListener('click', obj.clickHandler.bind(el));

// Without "bind", we need something like this:
var obj = {
    clickHandler: function() {
        var that = this;
        return function() {
            console.log(that);
        };
    }
};

el.addEventListener('click', obj.clickHandler.call(el));