Bootable refers to a storage device or medium that contains the necessary files and software to initiate the boot or startup process of a computer or operating system. A bootable device can include USB flash drives, internal or external hard drives, DVDs, or CDs that have been configured to contain a bootable version of an operating system or recovery tools.
Bootable media is commonly used for installing operating systems, running recovery utilities, or troubleshooting and repairing system issues.