how does switch work in javascript code example

Example 1: js switch case

switch(expression) {
  case x:
    // code block
    break;
  case y:
    // code block
    break;
  default:
    // code block
}

Example 2: javascript switch statement multiple cases

//javascript multiple case switch statement
var color = "yellow";
var darkOrLight="";
switch(color) {
    case "yellow":case "pink":case "orange":
        darkOrLight = "Light";
        break;
    case "blue":case "purple":case "brown":
        darkOrLight = "Dark";
        break;
    default:
        darkOrLight = "Unknown";
}

//darkOrLight="Light"

Example 3: javascript switch

let color = "black";

switch(color){
    case "red":
        console.log("color is red");
        break;
    case "white":
        console.log("color is white");
        break;
    case "black":
        console.log("color is black");
        break;
    default:
        console.log("unknow color");
}