Sometimes you want git to ignore certain files that appear on your machine. You can do this in 3 ways:

• Per project, in the project's .gitignore file
• Per project, in a local exclude file
• Globally on your machine

Downsides of per-project .gitignore entries

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While it might be tempting to set it per project (other devs might benefit from it), you

• need to do it each time for every project
• "pollute" a project's .gitignore file with stuff that may be quite irrelevant for others

A global ignore file for the rescue

You can just put your patterns into another file, in your home directory on your machine (e.g. ~/.gitignore).
Then, just feed it to git:

git config --global core.excludesfile ~/.gitignore

The file's effect will apply immediately if you do that from a repository. Neat.

Use cases for global ignores

• you're using a special editor that creates a hidden directory for config (e.g. VS Code)
• ignore a dir called untracked for your personal code snippets or project files like Excel sheets