Compare indexOf and includes

let string = "This is a string";

/**
 * Now we can check if 
 * string contains substring
 * using indexOf()
 * */
 
 if (string.indexOf("a") !== -1) {
     console.log("There is a substring");
 } else {
     console.log("Substring not found");
 }
 
 //Result:
 // "There is a substring"
 
 /**
  * Let's use includes() for
  * the same action
  * */
  
  if (string.includes("a")) {
      console.log("There is a substring");
  } else {
     console.log("Substring not found");
  }
 
  //Result:
 // "There is a substring"
 
 /**
  * Let's check if index is larger
  * or smaller than number
  * */
  
  if (string.indexOf("a") > 10) {
      console.log("A substring is too far");
  } else {
      console.log("A substring is close enough");
  }
  
  //Result:
  // "A substring is close enough"