What are Environment Variables, and how do I use them? (get,set)

12:25   Environment Variables Explained for Deployment: Secure Setup for Frontend & Backend 5:26   How to Use Environment Files (.env) in Node.js - Tutorial (dotenv) 0:42   How to use a .env file to load environment variables in a dev container 8:27   Lesson 64. Environment Variables: Backend (TypeScript, Node.js, React) 5:26   Frontend, API, Backend and Database explained 2:41   How the Backend works? Server, Application, Database, and API ( by CodeON Jason K ) 11:51   3.4 Hiding API Keys with Environment Variables (dotenv) and Pushing Code to GitHub 7:00   Lesson 100. Sharing Common Environment Variables Between Frontend and Backend 3:09   How Do Backend Applications Handle Environment Variables? 12:58   Backend web development - a complete overview 4:49   Setting Up PYODBC in your backend env 5:37   Learn How Companies Deploy Code to Production Environment [In 5 Mins!] 9:04   Lesson 130. Standardizing Shared Environment Variables for Frontend and Backend