Operators are special symbols that perform specific operations on one, two, or three operands, and then return a result. For example, the addition operator (+) adds two numbers and the multiplication operator (*) multiplies two numbers.

JavaScript has a wide range of operators, including arithmetic, assignment, comparison, logical, and more. Let's take a look at some examples:

Arithmetic Operators

The most common arithmetic operators are +, -, *, /, and %.

Here's an example of how to use them:

let a = 10;
let b = 5;

console.log(a + b); // Output: 15
console.log(a - b); // Output: 5
console.log(a * b); // Output: 50
console.log(a / b); // Output: 2
console.log(a % b); // Output: 0

Assignment Operators

Assignment operators are used to assign values to variables. The most common assignment operator is the equal sign (=), which assigns the value on the right to the variable on the left.

Here's an example:

let x = 10;
let y = 5;

x = y;
console.log(x); // Output: 5

JavaScript also has compound assignment operators, which combine a math operation and assignment.
For example, x += y is the same as x = x + y.

Comparison Operators

Comparison operators are used to compare two values and return a boolean value (true or false). The most common comparison operators are ==, !=, >, <, >=, and <=.

Here's an example:

let x = 10;
let y = 5;

console.log(x == y); // Output: false
console.log(x != y); // Output: true
console.log(x > y); // Output: true
console.log(x < y); // Output: false
console.log(x >= y); // Output: true
console.log(x <= y); // Output: false

Logical Operators

Logical operators are used to combine conditional statements. The most common logical operators are && (and), || (or), and ! (not).

Here's an example:

let x = 10;
let y = 5;

console.log(x > 0 && y > 0); // Output: true
console.log(x > 0 || y > 0); // Output: true
console.log(!(x > 0)); // Output: false

Expressions are combinations of values, variables, and operators that produce a result.
For example, the expression x + y is a combination of the values of x and y, and the operator +.

In JavaScript, you can use expressions as stand-alone statements or as part of a larger statement.
For example:

let x = 10;
let y = 5;

let result = x + y;
console.log(result); // Output: 15

if (x > y) {
  console.log('x is greater than y');
}

Where x > y and x + y are expressions.

I hope this tutorial has been helpful in introducing you to operators and expressions in JavaScript. Happy coding!