How do I remove untracked files from my Git repository?

Untracked files are files that Git does not know about. A simple way to delete these is using git-clean.

Preview untracked files with git clean -n.

# list untracked files
$ git clean -n
Would remove LICENSE
Would remove README.md

# list both files and directories
$ git clean -nd
Would remove LICENSE
Would remove README.md
Would remove script/
Would remove spec/

Use git clean -f  to permanently remove the files:

# remove untracked files
$ git clean -f
Removing LICENSE
Removing README.md

# remove both files and directories
$ git clean -fd
Removing LICENSE
Removing README.md
Removing script/
Removing spec/

Check the Full Official Documentation for more options.