BalenaEtcher is a free, open-source, cross-platform application for flashing OS images to SD cards and USB drives. It supports Windows, macOS, and Linux operating systems, and can be used to create bootable media for a variety of devices, including Raspberry Pi, BeagleBone, and other single-board computers. It includes a simple, user-friendly graphical interface that makes it easy to select an image file, and then flash it to the target drive. The app also includes a verification step to ensure that the write was successful, as well as support for resizing the target drive in order to fit the image. Additionally, the app supports drag-and-drop functionality, allowing users to quickly and easily transfer images to the target drive.