I created an angular project and pushed it in my github repository.
When I looked at the pushed files, the node_modules folder was missing, I didn't declare anywhere to ignore this folder, is this a default behavior? If yes then why?
Also, when I decided to delete all my repositories on github and create only one instead where I will check-in all my projects, once initializing git init and pushing changes, git started pushing node_modules folder for all projects and it took a lot of time.
What makes git ignore or not ignore the node_modules folder all by itself? I haven't set this configuration anywhere by myself.
Thank you.
git does not ignore node_modules by default. It ignores nothing by default. The angular cli adds node_modules to .gitignore, which caused git to ignore it. See https://stackoverflow.com/a/37187110/5666087 for more info, and see angular cli's github repo for the specific .gitignore file added. You will see that /node_modules is listed there.
You should not version control node_modules, because those are artifacts you can get easily with npm install or yarn install.
Creating a git repository outside of a angular project (e.g., in a new directory) does not add a .gitignore file, so node_modules is not ignored.