**Custom firmware** ("CFW") is a full software modification to your 3DS, comparable to "administrator access" on a computer. It allows you to do anything that the 3DS is physically capable of doing, rather than being limited by whatever Nintendo allows you to do.
* Bypassing the region lock, allowing you to play games from other regions
* Home menu customization, using community-created [themes and badges](https://themeplaza.art)
* Modification of games ("ROM hacks") through [LayeredFS](https://github.com/knight-ryu12/godmode9-layeredfs-usage/wiki/Using-Luma3DS'-layeredfs-(Only-version-8.0-and-higher))
* Save data editing, backup, and restore
* Emulation of older consoles, as well as native playback of DS and GBA games
* Installing your physical cartridges for digital use
This guide will install **boot9strap + Luma3DS custom firmware** on **unmodified/stock** 3DS/2DS devices. If you have installed custom firmware in the past, you should follow [these instructions](checking-for-cfw) to find the correct upgrade path for your console. A modern, boot9strap/Luma3DS-based setup is preferred over older setups (arm9loaderhax, menuhax) because it is more stable for modern homebrew and continues to be supported by the community.
* While the risks of bricking have been minimized over the years, **we are not responsible for anything that goes wrong with your device**. Incorrect file placement will not brick your device, but reckless behavior might.
* This guide will work on every retail device in the Nintendo 3DS family of consoles (including the New 3DS series and the 2DS), regardless of region or firmware.
* Following this guide alone should not result in data loss, but SD card corruption is always a possibility. You should make a backup of your SD card contents if you have important data.
* You will need a working SD card in your 3DS, as well as the ability to write files to the SD card. The 3DS can read SD cards formatted as MBR/FAT32.