Dotfiles

Files prefixed with a dot . are called dotfiles. They are hidden by default on Unix-based operating systems. Dotfiles are used to store any type of configuration. All the user configuration is stored in dotfiles somewhere in or under the home directory. A lot of applications store their configuration in the ~/.config/ directory.

It is recommended to make a Git repository to back up and sync configuration files. However, it is not recommended to make a Git repository directly in the home directory. A better alternative is to move configuration files into a separate directory like ~/dotfiles/. To make sure installed programs still have access to the configuration files, symbolic links to the configuration files can be made using Stow.

History

That dotfiles are invisible was an accident¹. A long time ago Unix decided to hide the . and .. directories because they exist in every directory. The implementation only checked if the first character of a file or directory name was a dot ., and hid it when that was the case:

if fileName[0] == "." {
    hideFile()
}

This results in every file and directory starting with a dot to be hidden. What they should have done is check if the filename is . or .. instead:

if fileName == "." || fileName == ".." {
    hideFile()
}