Javascript basic question.

    var ButtonHandler = function()
    {
        var me = this;
        
        this.click = function()
        {
            alert("Click");
            me.meClick(); // How It can find "me"!!?
        };
        this.meClick = function()
        {
            alert("meClick");
        };
    }; 
    var b = new ButtonHandler(); // me created and destroyed.

    function onBtnclick()
    {
        b.click();
        //ButtonHandler.prototype.click();
    }
}