Introduction to JavaScript Programming Concepts

Scripting Language

Lightweight programming language for automation tasks.

JavaScript

Programming code for dynamic web page interaction.

HTML Pages

Documents structured with HyperText Markup Language.

Dynamic Programming Language

Allows interactive and changing content on web pages.

Interpreted Language

Code executed line-by-line at runtime.

Object-Oriented Capabilities

Supports concepts like objects and inheritance.

LiveScript

Original name of JavaScript before rebranding.

Netscape 2.0

First browser to implement JavaScript in 1995.

HTML tag used to embed JavaScript code.

Section

Part of HTML where visible content is placed.

Section

Part of HTML for metadata and links.

JavaScript Frameworks

Libraries like jQuery and Node.js for development.

Client-Side JavaScript

Runs in the user's browser for interactivity.

Static HTML

Fixed content without user interaction capabilities.

CGI Server-Side Scripts

Traditional scripts executed on the server.

User Input Validation

Checking data entered by users before submission.

Immediate Feedback

Instant responses to user actions without page reload.

Increased Interactivity

Enhanced user experience through responsive interfaces.

Drag-and-Drop Components

Interactive elements allowing users to move items.

JavaScript Limitations

Lacks file access and multi-threading capabilities.

Security Reasons

Restrictions to protect user data and privacy.

Networking Applications

JavaScript cannot handle network communications directly.

Browser Compatibility

JavaScript runs on all modern web browsers.

Graphical User Experience

Visual interaction design for improved usability.

JavaScript

Lightweight, interpreted programming language for web interactivity.

Client Side Validation

Verifies user input before server submission.

Manipulating HTML Pages

Modifies HTML dynamically using JavaScript.

User Notifications

Creates dynamic pop-ups for website alerts.

Back-end Data Loading

Uses Ajax to load data without page refresh.

Presentations

Builds web-based slide presentations with libraries.

Node JS

JavaScript runtime for building scalable server applications.

JavaScript Syntax

Implemented within

Case Sensitivity

Identifiers must maintain consistent capitalization.

Comments in JavaScript

Supports C-style and C++-style comments.

Single-line Comment

Text after // is ignored by JavaScript.

Multi-line Comment

Text between / and / is ignored.

HTML Comment

Variable Declaration

Variables declared using the var keyword.

Hello World Example

Basic program outputting 'Hello World!'

JavaScript Libraries

Includes RevealJS and BespokeJS for presentations.

Dynamic Pop-ups

Alerts users with notifications on webpages.

Event Based Library

Node JS uses events for server applications.

JavaScript Statements

Placed within

Data Containers

Variables act as named containers for data.

Script Placement

Recommended to place

JavaScript Keywords

Reserved words with specific meanings in code.

Variable Naming

Care needed for consistent variable names.

Variable Declaration

Using 'var' to create variables.

Primitive Data Types

Basic types: Numbers, Strings, Booleans.

Numbers

Includes integers and floating-point values.

Strings

Text values enclosed in quotes.

Boolean

Represents true or false values.

Undefined Data Type

Variable declared but not assigned a value.

Null Data Type

Explicitly assigned no value.

Reserved Keywords

Special words with predefined meanings in JavaScript.

JavaScript Operators

Symbols for performing actions in JavaScript.

Arithmetic Operators

Used for mathematical calculations.

Addition Operator

Symbol '+' for summing values.

Subtraction Operator

Symbol '-' for finding differences.

Multiplication Operator

Symbol '*' for multiplying values.

Division Operator

Symbol '/' for dividing values.

Modulus Operator

Symbol '%' for finding remainders.

Assignment Operators

Used to assign values to variables.

Concatenation Operator

Symbol '+' for joining strings.

Concatenation Assignment

Appends string to existing string.

Increment Operator

Increases variable's value by one.

Decrement Operator

Decreases variable's value by one.

Floating-Point Format

64-bit representation of numbers by IEEE 754.

Example of Addition

x + y results in the sum.

Example of Subtraction

x - y results in the difference.

Example of Modulus

x % y results in the remainder.

Pre-increment

Increments variable, then returns its value.

Post-increment

Returns variable, then increments its value.

Pre-decrement

Decrements variable, then returns its value.

Post-decrement

Returns variable, then decrements its value.

Logical And

True if both operands are true.

Logical Or

True if at least one operand is true.

Logical Not

True if operand is false.

Comparison Equal

True if both values are equal.

Comparison Identical

True if values and types are equal.

Comparison Not Equal

True if values are not equal.

Comparison Not Identical

True if values or types differ.

Comparison Less Than

True if left value is less than right.

Comparison Greater Than

True if left value is greater than right.

Comparison Greater or Equal

True if left is greater or equal to right.

Comparison Less or Equal

True if left is less or equal to right.

If Statement

Executes code block if condition is true.

If...Else Statement

Executes one block if true, another if false.

If...Else If Statement

Handles multiple conditions in decision making.

Leap Year Condition

Year divisible by 400 or 4, not 100.

Variable Declaration

Defines a variable for use in code.

JavaScript Syntax

Rules governing structure of JavaScript code.

Conditional Code

Code executed based on true/false conditions.

Flow Chart

Visual representation of decision-making process.

JavaScript Alerts

Displays messages to users in pop-up boxes.

if statement

Executes code if a condition is true.

else if statement

Checks another condition if the first is false.

else statement

Executes code if no conditions are true.

switch statement

Tests a variable against multiple values.

case

Defines a value to match in a switch.