# Brace Expansion: Twelve Folders in One Line

Braces turn one word into many before a command runs, from a list such as {beach,city} or a range such as {01..12}, so mkdir makes a folder for every month in one line and cp file{,.bak} makes a quick backup.

![Cheat sheet for the lesson Brace Expansion: Twelve Folders in One Line: Braces turn one word into many before a command runs, from a list such as {beach,city} or a range such as {01..12}, so mkdir makes a folder for every month in one line and cp file{,.bak} makes a quick backup.](https://fsdtrainingmedia.blob.core.windows.net/public/images/2026/11/faa8b13e5e344b3084febb6ff2b801dd.webp)

- Category: Bash
- Level: Apprentice
- Tags: brace-expansion, linux, mkdir, unix, wildcard
- Updated: November 10, 2026

Source: https://www.ask-codey.com/cheat-sheets/bash-brace-expansion-cheat-sheet