an Entity references as follows:
Expandable storage is a form of computer storage that is designed to be inserted and removed from a system. Some forms of removable media, such as optical discs, require a reader to be installed in the computer, while others, such as USB flash drives, have all the hardware required to read them built into the device, so only need a driver to be installed in order to communicate with the device. Using removable media poses some risks, including data theft and the introduction of malware. Examples of media that require a reader include: