If you want to re-format an external hard drive (a drive you plug into your computer, instead of installing inside of your computer) or flash drive, it's extremely easy to do.

You can format an external drive quickly and easily in Windows, without the need of any third-party tools. But before you format your USB drive, you need to consider which file system to use.

While the Mac can use a hard drive formatted for Windows, some features may be limited. So it's a good idea to format a new hard drive specifically for macOS.