execution context in module pattern

dog-definition.js

var dog = (function () {
    var nombre = "dog";

    var setName = function (newName) {
        nombre = newName;
    };

    var speak = function () {
        console.log('[' + nombre + ']: woof!');
    };

    // punto a
    return {
        setName : setName,
        speak : speak
    };
})();