If statement comparing numbers

IfNumbers.java

public static void main(String[] args) {
  
  // Variables
  Scanner input = new Scanner(System.in);
  int age;

  // Ask a question and save their answer
  System.out.print("Enter your age: ");
  age = input.nextInt();
  
  // Output text based on their answer
  if (age >= 18) {
    System.out.println("You can vote.");
  }
  else {
    // If the if statement above doesn't run, then this code will run
    System.out.println("You aren't old enough to vote.");
  }
}

The most common mistake using if statements and comparing numbers is knowing when to use = and when to use ==.
Use = when you want to set a variable to a number, like "int num = 5;"
Use == when you are comparing two numbers, like "num == 7;" This would return True if num = 7, but it would return False if num = 8 (or any other number but 7).