Uploading your work to GitHub
GitHub (https://github.com/) is a popular web-based system for storing and managing source code. While there are several alternatives, GitHub is particularly popular with people writing and sharing open source Python code, and this is the source code management system that we will use in this book.
Before delving into the specifics of GitHub, let's start by looking at how source code management systems work in general and why you might want to use one.
Imagine that you are writing a complex module and have opened your module in a text editor to make a few changes. While making these changes, you accidentally select 100 lines of code and press the Delete key. Before you realize what you've done, you save and close the file. Too late: those 100 lines of text are gone.
Of course, you might (and hopefully will) have a backup system in place which keeps regular backups of your source files. But if you had made changes to some of the missing code in the past few minutes...