what is switch statement in progrgraming code example

Example 1: switch case in

function whatToDrink(time){
    var drink ;
          switch (time) {
            case "morning":
              drink = "Tea";
              break;
            case "evening":
              drink = "Shake";
              break;
            default:
              drink="Water";   
          }
  	return drink;
}
console.log(whatToDrink("morning")) //Tea
console.log(whatToDrink("evening")) //Shake
console.log(whatToDrink("night"))   //Water
console.log(whatToDrink("daytime")) //Water

Example 2: switch case c

switch(expression) {

   case constant-expression  :
      statement(s);
      break; /* optional */
	
   case constant-expression  :
      statement(s);
      break; /* optional */
  
   /* you can have any number of case statements */
   default : /* Optional */
   statement(s);
}