Definition - What does Legacy Device mean?
A legacy device refers to a computing device or equipment that is outdated, obsolete or no longer in production. This includes all devices that are unsupported or no longer commonly used by most devices and software applications.
Techopedia explains Legacy Device
Typically, a legacy device consists of non plug-and-play (PnP) devices that lack a peripheral controller interface (PCI) and requires manual configuration and jumper installation. A legacy device also includes computing equipment rendered obsolete by modern technologies.
For example, because CD drives replaced floppy disk drives, there are few new computers distributed with built-in floppy drives. Similarly, native legacy devices are not supported by most modern software applications.