Powers of Data Storage

First, let us clarify that disk space and memory (RAM) are two different things.  
Think of disk space as a car's trunk and memory as the car's engine...

• Disk space is the computer's capacity (storage) for installing new applications and saving data.  
• Memory is the computer's capability (muscle) to open (run) those stored applications and data files. 

See how much for more information, but with that out of the way. The numbers below are approximates.

• Bit: The basic unit of information in a binary numbering system. The electronic circuitry in computers detect the difference between two states represented 1 or 0 (on or off, true or false).    
  • Eight bits is an octet, a.k.a. a byte.
• 1 Byte (8 bits) required for a single character: A, B, C, D, 1, 2, 3, @, #, $ and so on 
• Kilobyte A thousand bytes. Actually 1,024 bytes (2^10).
  • 2 Kilobytes: A single typewritten page (plain text)
  • 5 Kilobytes: The page you are currently reading (less the header)
  • 300 Kilobytes: A typical low resolution digital photograph saved as a JPG
• Megabyte (1,048,576 bytes or 1,024 Kilobytes, i.e. each thousand Kb is one Mb)
  • One 3.5 inch floppy disk (actually holds about 1.38Mb)
  • 2 Megabytes: A single medium resolution photograph
  • 5 Megabytes: A typical smart phone photograph, a 30 seconds of TV-quality video
  • 10 Megabytes: A minute of high-fidelity sound
  • 200 Megabytes: Our entire web site including all images and databases.
  • 700 Megabytes: A Typical CD-ROM.  Approximately 80 minutes of music
• Gigabyte (1,073,741,824 bytes or ~1,073,741 Kilobytes or ~1,074 Megabytes)
  • 1 Gigabyte: A pickup truck filled with printed paper -or- A movie at TV quality
  • 2 Gigabytes: 20 meters of shelved books 4.6 Gigabyte: a full DVD CD
  • 25 Gigabytes: a Blu-ray CD
  • 40 Gigabytes: A large hard drive for a home PC (2000-2001)
  • 80 Gigabytes: A large hard drive for a home PC  (2002-2003)
  • 120 Gigabytes: A large hard drive for a home PC (2004-2006)
  • 500 Gigabytes: A large hard drive for a home PC (~2010)
  • 750 Gigabytes: A typical hard drive (~2014)
• Terabyte (1,099,511,627,776 bytes)
  • 1 Terabyte: A large hard drive for a home PC (2014) and typical in 2016
  • 1 Terabyte: All the X-ray films in a large technological hospital
  • 10 Terabytes: The entire printed collection of the US Library of Congress  
• Petabyte (1,125,899,906,842,624 bytes)
  • 1 Petabyte: 3 years of EOS data (2001)
  • 200 Petabytes: All printed material
  • 500 Petabytes: All online data by the year 2000
• Exabyte (1,152,921,504,606,846,976 bytes)
  • 5 Exabytes: All words ever spoken.  
• Zettabyte 1, 000, 000, 000, 000, 000, 000, 000 bytes
• Yottabyte 1, 000, 000, 000, 000, 000, 000, 000, 000 bytes

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