Computer Science Principles
Course Progress
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Objectives in LxD
3.4 Strings
3.4 Strings
3.3 Mathematical Expressions
3.3 Math Expressions
3.2 Data Abstractions
3.2 Data Abstractions
3.1 Variables & Assignments
3.1 Variables and Assignments
3.1 Variables and Assignments (Sample)
Intro to Python
Intro to Javascript
Variables and HTML DOM (Sample)
3.5 Boolean Expressions (PY)
3.5 Boolean Expressions (JS)
3.8 Iterations
3.7 Nested Conditionals
3.6 Conditionals
3.8 Iterations
3.7 Nested Conditionals
3.6 Conditionals
3.13 Developing Procedures
3.12 Calling Procedures
3.10 Lists
3.13 Developing Procedures
3.10 Lists
3.9 Developing Algorithms
3.17 Algorithmic Efficiency
3.9 Algorithms
3.17 Algorithmic Efficiency
3.15 Random Numbers (pseudocode)
3.15 Random Numbers (js)
3.15 Random Numbers (py)
BI 3 Review
Sprint View
Week 4
Intro to Javascript
Intro to Javascript
1 min read
JavaScript Overview
JavaScript is a high-level, interpreted programming language primarily known for enabling interactive and dynamic content on the web. It runs directly inside web browsers, which means developers can update a page’s content, control multimedia, animate elements, and handle user input without needing to reload the entire page.
Why JavaScript is Used
- Client-Side Interactivity: Allows real-time user interactions like form validation, animations, and interactive menus.
- Rich Ecosystem: A vast library and framework ecosystem (React, Vue, Angular, Express) accelerates development.
Unique Use Cases
- Building Single-Page Applications (SPAs) that behave like desktop apps
- Creating real-time chat applications using WebSockets
- Developing cross-platform mobile apps with frameworks like React Native
- Game development for browsers using WebGL or Canvas APIs
- Internet of Things (IoT) devices with lightweight Node.js servers
Distinct Properties
- Dynamic Typing: Variables can hold values of any type at runtime.
- Prototype-Based Inheritance: Objects inherit directly from other objects rather than through classical classes (though ES6 class syntax exists).
- Event-Driven and Asynchronous: Uses an event loop with callbacks, promises, and async/await for non-blocking operations.
- First-Class Functions: Functions can be stored in variables, passed as arguments, and returned from other functions.
Core Concepts
- Variables & Scope:
var,let, andconstkeywords define variables with different scoping rules. - Data Types: Includes primitives (Number, String, Boolean, Null, Undefined, Symbol, BigInt) and objects.
- Functions & Closures: Functions can capture variables from their surrounding scope, forming closures.
- Objects & Prototypes: Object-oriented features are built on prototypes rather than classical inheritance.
- DOM Manipulation: Directly interact with and modify HTML/CSS for responsive web pages.
- Asynchronous Programming: Handle tasks like API calls using callbacks, promises, and async/await to avoid blocking the main thread.
Summary
JavaScript’s versatility—running in browsers, servers, and even embedded devices—combined with its event-driven, asynchronous model and rich ecosystem make it a cornerstone of modern software development. “””