Data Storage Capacity

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Data storage capacity refers to how much data can be saved in a storage device.  Different storage devices have different capacities.  Some have small data capacity while others have huge data capacity.

Data Storage

In layman’s terms, storage is a place where you put things for safekeeping or for future use.  In technical terms, data storage refers to a device where data is saved.  It is connected to the computer through an input / output (I/O) process.  It allows a computer to hold data, either temporarily or permanently.  Data is saved either in electromagnetic or optical form.  The data saved can be retrieved by using a computer.

Types of Storage

There are two options for data backup: Local and Remote Storage Options.  Under the Local Storage Option are the following types of storage:

  • External Hard Drive – is like a hard drive installed in a computer the only difference is that this hard drive can be plugged and removed from the computer.
  • Solid State Drive (SSD) – looks like a hard drive but inside it has no moving parts.
  • Network Attached Storage (NAS) – is one or more regular IDE or SATA hard drives connected to a network hub.
  • USB Thumb Drive or Flash Drive – is like an SSD but smaller in size and capacity.
  • Optical Drive (CD / DVD) – ideal for storing media and software for distribution.

Under the Remote Storage Option, there’s only one type of storage which is the Cloud Storage.  It’s a storage space that can be accessed from any computer with internet connection.

Data Storage Evolution

Over the years, data storage has evolved and progressed.  Below is a chronological list of data storage evolution:

Year Data Storage
1745 Punch Cards
1950 Magnetic Tape
1962 Cassette Tape
1963 Removable Hard Drive
1966 Punched Tape
1971 Floppy Disk
1982 CD-ROM
1990 CD-RW
1994 Zip Drive
1995 DVD-R
1999 SD Card
2000 USB Flash Drive
2007 Cloud

Data Storage Capacity Measurement

Data storage capacity is measured in bits (b) and bytes (B).  One bit is equivalent to one single binary value which is either 1 or 0.  One byte is equivalent to 8 bits.   One kilobyte (KB) is equivalent to 1,024 bytes.  One megabyte (MB) is equivalent to 1,024 KB.  One gigabyte (GB) is equivalent to 1,024 MB.  One terabyte (TB) is equivalent to 1,024 GB.  One petabyte (PB) is equivalent to 1,024 TB.  One exabyte (EB) is equivalent to 1,024 PB.

Data Storage Capacity Examples and Illustration

An example of a small data capacity storage device is a floppy disk that can hold 1.44 MB of data.  Though 1.44 MB of data seems small compared to millions and millions of data, 1.44 MB is still equivalent to more than a million characters.  An example of huge data capacity storage device is a hard drive that can hold 1 TB of data.
To easily picture out how much data is stored, here’s an illustration:

Number of Bytes Object
1 byte (B) A single letter or number
100 kilobytes (KB) A low-resolution picture
1 megabyte (MB) A short paperback
1 gigabyte (GB) A pickup truck full of books
1 terabyte (TB) 50,000 trees worth of printed paper
1 petabyte (PB) 3 years’ worth of NASA’s Earth Observing System data
5 exabytes (EB) All words spoken by men

Latest on Data Storage

The holographic data storage is currently being developed.  It has a potential to store 1 TB of data in a 1 cm hologram.  It is also known as the 3-D data storage.
Although there’s none using Zettabyte and Yottabyte currently, these are possible storage capacities in the future.  One zettabyte (ZB) is equivalent to 1,024 EB.  One yottabyte (YB) is equivalent to 1,024 ZB.