Javascript Expressions

In JavaScript, an expression is a unit of code that evaluates to a single value. This value can be of any data type, such as a number, string, boolean, object, or function.

Literals

Example

Run Code
5; // A number literal, evaluates to 5
"hello"; // A string literal, evaluates to "hello"
true; // A boolean literal, evaluates to true
null; // The null literal, evaluates to null

Variable References

Example

Run Code
let x = 10;
x; // Evaluates to the value of x, which is 10

Arithmetic Expressions

Example

Run Code
5 + 3; // Evaluates to 8
10 * 2; // Evaluates to 20
(15 - 5) / 2; // Evaluates to 5

String Concatenation

Example

Run Code
"Hello" + " " + "World"; // Evaluates to "Hello World"

Comparison Expressions

Example

Run Code
5 > 3; // Evaluates to true
"apple" === "orange"; // Evaluates to false

Logical Expressions

Example

Run Code
true && false; // Evaluates to false
(10 > 5) || (20 < 10); // Evaluates to true

Function Calls

Example

Run Code
function add(a, b) {
  return a + b;
}
add(2, 3); // Evaluates to 5

Function Expressions

Example

Run Code
let greet = function() {
  return "Greetings!";
};
greet(); // Evaluates to "Greetings!"

Ternary Operator

Example

Run Code
let age = 18;
let status = (age >= 18) ? "Adult" : "Minor"; // Evaluates to "Adult"

Array and Object Literals

Example

Run Code
[1, 2, 3]; // Evaluates to an array
{ name: "Alice", age: 30 }; // Evaluates to an object