Operators allow you to tell your script exactly how a piece of data should interact with another piece of data. For example, if you wanted to add 2 pieces of data, then you would use the plus sign ( + ) operator. Here’s how that would look like.

1 | 5 + 5 |

There are many kinds of operators such as math operators, assignment operators, and comparison operators. Let’s take a look at each of these.

## Math Operators

These are the most common operators you’ll be using. Math operators allow you to add, subtract, divide and multiply data together. In JavaScript this is how you would use them.

1 2 3 4 5 | var num1 = 3 + 3; // Addition var num2 = 3 - 3; // Subtraction var num3 = 3 / 3; // Division var num4 = 3 * 3; // Multiplication var num5 = 4 % 3; // Modulus |

You should be familiar with all these operators. The only operator that you may not know about is the modulus math operator. This is the very last operator used in our code. It’s represented by the * %* sign.The value that is returned is the remainder. For example, if you divide 3 by 3, you get 0. However, if you divide 4 by 3, you get 1 with a remainder of 1. You’re returned the remainder 1. We’ll learn how this can be useful in a future tutorial.

## Assignment Operators

You’ve already used an assignment operator. It’s the equal sign ( = ). Assignment operators allow you to set a value for a certain variable. There are a couple of other assignment operators you could use.

Here are examples of them.

1 2 3 4 5 6 | var num6 = 3; num6 += 3; // 6 : Addition num6 -= 3; // 3 : Subtraction num6 /= 3; // 1 : Division num6 *= 3; // 3 : Multiplication num6 %= 3; // 0 : Modulus |

You’ll notice that we’re using the math operators combined with the assignment operators. This is simply a shortcut. If you’re manipulating the current value of a variable with a new value, then you can use this as a shortcut.

You just type in the math operator before the assignment operator to do so. In the example above, there’s a variable named * num6 *with the initial value of 6. The next line adds 3 to the current value resulting in 6.

## Adding Strings Together

You can also add strings together like so.

1 2 | var add_string = 'This is a ' + 'string'; // This is a string var num_string = 'This is a ' + 5; // This is a 5 |

When you add these 2 strings together. You get 1 combined string. If you try adding a number and a string together, you’ll get back a string. This technique is calling appending. We’re appending 1 string onto another string to make one bigger string.

## Conclusion

We haven’t talked about comparison operators yet. We will in a future tutorial when we talk about conditional statements. You’ll find yourself using operators everyday.