Etcher is a disk image writer and operating system flashing tool used to create bootable USB drives and SD cards. It transfers binary system images to physical external media, enabling computers or microcontrollers to boot from the prepared storage.
The application includes system drive protection to prevent the accidental erasure of internal hard drives by filtering available storage devices based on metadata. It also performs data verification by comparing written bytes against the source image to ensure no corruption occurred during the flashing process.