Categories of auxiliary storage are?

1. Hard disk drives (HDD)
2. Solid-state drives (SSD)
3. Optical storage devices (CDs, DVDs, Blu-ray discs)
4. USB flash drives
5. Memory cards (SD cards, microSD cards)
6. External hard drives
7. Network-attached storage (NAS)
8. Cloud storage services

- Magnetic tape: Magnetic tape is a long, thin strip of plastic that is coated with a magnetic material. Data is stored on the tape by magnetizing the material in different ways. Magnetic tape is a relatively inexpensive form of storage, but it is also slow to access.
- Optical disks: Optical disks are circular disks that are coated with a reflective material. Data is stored on the disks by burning small pits into the material. Optical disks are more expensive than magnetic tape, but they are also much faster to access.
- Solid-state drives (SSDs): SSDs are electronic storage devices that use flash memory to store data. Flash memory is a type of non-volatile memory that can store data even when the power is turned off. SSDs are the fastest type of auxiliary storage, but they are also the most expensive.
- Cloud storage: Cloud storage is a service that allows users to store data on remote servers over the internet. Cloud storage is a convenient and affordable way to store data, but it is also less secure than local storage.