Functions are a kind of subroutine that performs a specific task. Like every other programming language, **JavaScript** has its own rules for declaring functions. Some syntax may seem familiar; however, there are a few things to notice.

# Syntax
The `function` keyword is placed before the name of the new function to indicate that a new function is being declared. Curly braces `{}` are used to indicate the function’s body, like most other languages. 

``` javascript
function HelloWorld(args){
    // your code
}
```

function HelloWorld(){
  console.log("Hello World");
}

HelloWorld();

codemirror

console

# Anonymous function
In JavaScript, we can make functions without a name called **anonymous functions**. In the example below, the variable `HelloWorld` can lose the function declaration and be replaced by any other value. 

var HelloWorld = function (){
  console.log("Hello World");
}

HelloWorld();

# Lambda Functions
Lambda functions are similar to anonymous functions, but they have more flexible features and syntax. An `arrow function` is another of this type of function.

```
var functionName = (parameters) => // function body
```

var HelloWorld =  () =>
  console.log("Hello World");

HelloWorld();

Javascript functions

Syntax

Code

Anonymous function

Lambda Functions