# 0.85-inch drive

> hard drive form factor

**Wikidata**: [Q123185216](https://www.wikidata.org/wiki/Q123185216)  
**Source**: https://4ort.xyz/entity/0-85-inch-drive

## Summary
The 0.85-inch drive is a hard drive form factor designed for compact data storage, notable for its small size and use in specialized applications. It is classified under the broader category of disk drives and is exemplified by devices like the Toshiba MK4001MTD. This form factor represents an effort to miniaturize storage technology while maintaining functional capabilities.

## Key Facts
- **Form Factor**: 0.85-inch drive is a specific hard drive form factor, distinct from larger formats like 2.5-inch or 3.5-inch drives.
- **Classification**: Subclass of "drive" and instance of "drive form factor" in taxonomic hierarchies.
- **Related Device**: The Toshiba MK4001MTD is a documented example of a 0.85-inch hard drive.
- **Aliases**: Also referred to as "0.85″ drive" or "0.85″ hard disk."
- **Documentation**: Described in resources such as [obsoletemedia.org](https://obsoletemedia.org/0-85-inch-hard-disk/).
- **Imagery**: Visual representation available via Wikimedia Commons ([Toshiba microdrive.jpg](https://commons.wikimedia.org/wiki/Special:FilePath/Toshiba_microdrive.jpg)).

## FAQs
### Q: What is the 0.85-inch drive used for?
A: The 0.85-inch drive was designed for compact data storage, typically in specialized or space-constrained devices, though specific applications are not detailed in primary sources.

### Q: Is the 0.85-inch drive still in use today?
A: The 0.85-inch drive is considered obsolete, as indicated by its documentation on archival resources like obsoletemedia.org, and has been succeeded by newer storage technologies.

### Q: How does the 0.85-inch drive compare to other form factors?
A: It is significantly smaller than traditional 2.5-inch or 3.5-inch hard drives, reflecting an early attempt to reduce storage device dimensions while maintaining mechanical functionality.

## Why It Matters
The 0.85-inch drive signifies a niche innovation in data storage miniaturization, addressing the need for compact solutions in an era of advancing technology. While not widely adopted, it represents a transitional phase in the evolution of storage devices, bridging the gap between mechanical hard drives and later solid-state solutions. Its existence highlights the ongoing challenge of balancing storage capacity with physical size, a critical consideration in consumer electronics and specialized hardware. Though obsolete today, studying this form factor provides insight into the iterative process of technological development and the risks of investing in non-standard formats.

## Notable For
- **Unique Form Factor**: One of the smallest mechanical hard drive formats developed, emphasizing miniaturization.
- **Toshiba Implementation**: The MK4001MTD model serves as a tangible example of this form factor in practice.
- **Niche Obsolescence**: Documented on platforms like obsoletemedia.org, underscoring its status as a specialized, discontinued technology.

## Body
### Definition and Classification
The 0.85-inch drive is a **hard drive form factor** categorized under the broader class of "drive" and "disk drive." It is defined by its physical dimensions, which are smaller than conventional formats, and its function as a data storage device using rotating disks.

### Technical Context
- **Form Factor Significance**: The 0.85-inch specification refers to the physical size of the drive, a critical factor in device design and compatibility.
- **Mechanical Operation**: As a subset of disk drives, it relies on spinning disks and read/write heads, distinguishing it from solid-state storage technologies.

### Related Entities
- **Toshiba MK4001MTD**: A specific implementation of the 0.85-inch form factor, illustrating its application in real-world hardware.

### Historical and Cultural Context
- **Documentation and Legacy**: The drive’s inclusion on obsoletemedia.org and Wikimedia Commons reflects its status as a historical artifact of storage technology, preserved for archival and educational purposes.