1. if Statement:

• Use if to specify a block of code to be executed, if a specified condition is true

  if (condition) {
    //  block of code to be executed if the condition is true
  }
  

  let x = 9;
  if (x > 2) {
      console.log("x is greater than 2");
  }
  

2. if-else Statement:

• Use else to specify a block of code to be executed, if the same condition is false

  if (condition) {
    //  block of code to be executed if the condition is true
  } else {
    //  block of code to be executed if the condition is false
  }
  

  let x = 9;
  if (x > 2) {
      console.log("x is greater than 2");
  } 
  else {
      console.log("x is not greater than 2");
  }
  

  3. if-else if-else Statement:

• Use else if to specify a new condition to test, if the first condition is false

  if (condition1) {
    //  block of code to be executed if condition1 is true
  } else if (condition2) {
    //  block of code to be executed if the condition1 is false and condition2 is true
  } else {
    //  block of code to be executed if the condition1 is false and condition2 is false
  }
  

  let x = 9;
  if (x > 10) {
      console.log("x is greater than 10");
  } 
  else if (x > 2) {
      console.log("x is greater than 2 but not greater than 10");
  } 
  else {
      console.log("x is not greater than 2");
  }
  

  4. switch Statement:

• Use switch to specify many alternative blocks of code to be executed

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

  let day = "Monday";
  switch (day) {
      case "Monday":
          console.log("It's the start of the week");
          break;
      case "Sunday":
          console.log("It's weekend");
          break;
      default:
          console.log("It's a regular day");
  }
  

  5. Ternary (Conditional) Operator:

  let age = 19;
  let message = (age >= 18) ? "You are ready to vote" : "You cannot vote";
  console.log(message);
  

  6. Truthy and Falsy Values:

  let truthyValue = "Hello"; // Truthy
  let falsyValue = 0; // Falsy
  if (truthyValue) {
      console.log("Truthy value");
  }
  if (!falsyValue) {
      console.log("Falsy value");
  }