Data storage is the collective methods and technologies that capture and retain digital information on electromagnetic, optical or silicon-based storage media.
Storage is a key component of digital devices, as consumers and businesses have come to rely on it to preserve information ranging from personal photos to business-critical information.
Storage is frequently used to describe the devices and data connected to the computer through input/output (I/O) operations, including hard disks, flash devices, tape systems and other media types.
Why data storage is important
Underscoring the importance of storage is a steady climb in the generation of new data, which is attributable to big data and the profusion of internet of things (IoT) devices. Modern storage systems require enhanced capabilities to allow enterprises to apply machine learning-enabled artificial intelligence (AI) to capture this data, analyze it and wring maximum value from it.
Larger application scripts and real-time database analytics have contributed to the advent of highly dense and scalable storage systems, including high-performance computing storage, converged infrastructure, composable storage systems, hyper-converged storage infrastructure, scale-out and scale-up network-attached storage (NAS) and object storage platforms.
By 2025, it is expected that 163 zettabytes (ZB) of new data will be generated, according to a report by IT analyst firm IDC. That estimate represents a potential tenfold increase from the 16 ZB produced through 2016.
How data storage works
The term storage may refer both to a user’s data generally and, more specifically, to the integrated hardware and software systems used to capture, manage and prioritize the data. This includes information in applications, databases, data warehouses, archiving, backup appliances, and cloud storage.
Digital information is written to target storage media through the use of software commands. The smallest unit of measure in a computer memory is a bit, described with a binary value of 0 or 1, according to the level of electrical voltage contained in a single capacitor. Eight bits make up one byte.
Other capacity measurements to know are:
- kilobit (Kb)
- megabit (Mb)
- gigabit (Gb)
- terabit (Tb)
- petabit (Pb)
- exabit (Eb)
Larger measures include:
- kilobyte (KB) equal to 1,024 bytes
- megabyte (MB) equal to 1,024 KB
- gigabyte (GB) equal to 1,024 MB
- terabyte (TB) equal to 1,024 GB
- petabyte (PB) equal to 1,024 TB
- exabyte (EB) equal to 1,024 PB
Few organizations require a single storage system or connected system that can reach an exabyte of data, but there are storage systems that scale to multiple petabytes.
Data storage capacity requirements define how much storage is needed to run an application, a set of applications or data sets. Capacity requirements take into account the types of data.
For instance, simple documents may only require kilobytes of capacity, while graphic-intensive files, such as digital photographs, may take up megabytes, and a video file can require gigabytes of storage. Computer applications commonly list the minimum and recommended capacity requirements needed to run them.https://www.youtube.com/embed/f3BNHhfTsvk
This video from CHM Nano Education explains
the role of magnetism in data storage.
On an electromechanical disk, bytes store blocks of data within sectors. A hard disk is a circular platter coated with a thin layer of magnetic material.
The disk is inserted on a spindle and spins at speeds of up to 15,000 revolutions per minute (rpm). As it rotates, data is written on the disk surface using magnetic recording heads.
A high-speed actuator arm positions the recording head to the first available space on the disk, allowing data to be written in a circular fashion.
A sector on a standard disk is 512 bytes. Recent advances in disk include shingled magnetic recording, in which data writes occur in overlapping fashion to boost the platter’s areal density.
On solid-state drives (SSDs), data is written to pooled NAND flash, designed with floating gate transistors that enable the cell to retain an electrical charge. An SSD is not technically a drive, but it exhibits design characteristics similar to an integrated circuit, featuring potentially millions of nanotransistors placed on millimeter-sized silicon chips.
Backup data copies are written to disk appliances with the aid of a hierarchical storage management system. And although less commonly practiced than in years past, the tactic of some organizations remains to write disk-based backup data to magnetic tape as a tertiary storage tier. This is a best practice in organizations subject to legal regulations.
A virtual tape library (VTL) uses no tape at all. It is a system in which data is written sequentially to disks, but retains the characteristics and properties of tape. The value of a VTL is its quick recovery and scalability.