SOURCE

var colors = ["red", "green", "blue"];
var removed = colors.splice(0, 1);
console.log(colors); // green,blue
console.log(removed); // red

removed = colors.splice(1, 0, "yellow", "orange");
console.log(colors); // green,yellow,orange,blue
console.log(removed); // ""

removed = colors.splice(1, 1, "red", "purple");
console.log(colors); // green,red,purple,orange,blue
console.log(removed); // yellow