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Post: Learn about JavaScript FUNCTIONS
Lesson Plan: Introduction to JavaScript Functions
Lesson Objectives:
By the end of this lesson, students will be able to:
- Understand what a function is in JavaScript.
- Know how to create and call functions.
- Use JavaScript built-in functions such as
alert()
. - Pass arguments to functions.
- Understand the difference between arguments and parameters.
Key Concepts:
- JavaScript Function: A block of reusable code that performs a specific task.
- Function Definition: Consists of the
function
keyword, a name, parentheses (for arguments), and curly braces for the code block. - Calling a Function: The process of executing the code inside a function.
- Arguments: Values passed to functions for it to operate on.
- Built-in Functions: Predefined JavaScript functions such as
alert()
.
Introduction to Functions:
1. Defining Functions
- Explain that a function is a reusable block of code that performs a specific task.
- Example:
- Explain how this function, when called, will trigger a popup with “Password!” message.
2. Calling Functions
- A function must be called in order to execute.
- Example:
3. Function Structure:
- A function needs:
- The
function
keyword: To define the function. - A name: Helps describe what the function does (e.g.,
sayPassword()
). - Curly braces
{}
: To enclose the code block. - Statements: The actual task the function performs (in this case, the alert).
- Function call: To invoke the function.
- The
JavaScript Built-in Functions:
- JavaScript comes with built-in functions like
alert()
. This saves time since the work is already done for you.
Example:
Passing Arguments to Functions:
1. Introduction to Arguments
- Arguments are values we pass to functions to perform specific tasks.
- The
alert()
function requires an argument to know what message to display.
Example: