A storage device is a hardware component used to store digital data. Common types include hard disk drives (HDD), solid-state drives (SSD), and USB flash drives. These devices allow users to save files, applications, and operating systems, making it possible to access and retrieve information when needed. Storage devices can be internal, like those found inside a computer, or external, such as portable drives. They vary in capacity, speed, and technology, catering to different needs, from everyday file storage to high-performance data processing in servers and data centers.