ELI5 - What is Git-hub?

Imagine you and your friends are building something together, like a big Lego castle. You all want to help, but if everyone grabs pieces at the same time, things can get messy. Pieces get lost. Someone breaks a wall. Nobody remembers how it looked yesterday. GitHub is like a smart playroom that keeps the Lego castle safe while everyone works on it.

GitHub is a place on the internet where people store code. Code is just written instructions that tell computers what to do. Websites, apps, and games are all made from code. GitHub keeps this code in neat boxes called repositories. You can think of a repository as a project folder. Inside are all the files needed to build something. One of the most important jobs GitHub does is remembering every change. Every time someone edits the code, GitHub takes a snapshot. This snapshot is called a commit. If something breaks later, you can go back in time and see how things looked before. You can even undo mistakes. That makes people feel safe when they experiment.

GitHub also helps people work together without stepping on each other. Each person can make their own copy of the project. They can change things in their copy and test them. When they are happy, they ask to add their changes back to the main project. This request is called a pull request. Other people can look at it, talk about it, and suggest fixes before it becomes part of the main work. Another helpful thing GitHub does is act like a notebook. People write notes about what the project does and how to use it. They also keep lists of problems to fix or ideas to add later. This makes it easier for new people to join and understand what is going on. GitHub is not just for experts. Beginners use it too. It teaches good habits, like saving work often and explaining changes clearly. Many teachers use it. Many companies use it. Some of the biggest programs in the world are built with it, by people who may never meet in person.

So in simple terms, GitHub is a shared home for code. It keeps things organized. It remembers everything. It helps people work together calmly instead of chaotically. It is like a time machine, a filing cabinet, and a teamwork helper all rolled into one.