Category:

# What is a Petabyte?

A petabyte is about a million gigabytes, each of which can hold the information equivalent of about 1,000 thick books.
Article Details
• Written By: R. Kayne
• Edited By: Niki Foster
• Last Modified Date: 08 September 2015
2003-2015
Conjecture Corporation
Free Widgets for your Site/Blog
 Charles Darwin let his children draw on the reverse sides of his draft of "On the Origin of Species."  more...

 October 8 ,  1970 :  US President Nixon's peace proposal was rejected by North Vietnamese and Viet Cong negotiators.  more...
wiseGEEK Slideshows

In the world of ever-growing data capacity, a petabyte represents the frontier just ahead of the terabyte, which itself runs just ahead of the gigabyte. In other words, 1,024 gigabytes is one terabyte, and 1,024 terabytes is one petabyte. To put this in perspective, a petabyte is about one million gigabytes (1,048,576).

In the late 1980s, a large hard disk was considered 80 megabytes. Today, that amount of space doesn’t even hold a current Windows operating system without butting up against storage limits. Robust programs, music files, digital versatile discs (DVDs), streaming video and high-resolution graphics have all become memory-hungry beasts devouring real estate bit by byte. It would have been unthinkable in the 1980s that the home computer would one day require tens and even hundreds of gigabytes to store data. Though the petabyte still lies beyond the territory of the terabyte, who can say where the home computer will be in another two decades?

It’s a humbling thought that the mighty petabyte stores individual bits. It takes eight bits to make a byte, which represents a single character. The word “bit” for example, takes 24 bits to spell, or three bytes.

Put 1,024 bytes together and you have a kilobyte. Take the same amount of kilobytes (1,024) and you’ve built a megabyte; 1,024 megabytes and you have a gigabyte – and so on to get a terabyte, and finally, a petabyte. So how many bits are in a petabyte? A staggering 9,007,199,254,740,990!

For the average person, the number crunching gets a little hairy when moving into the territory of the petabyte, but it doesn’t stop there. Beyond the petabyte are the exabyte, zettabyte and yottabyte. While some may still be getting used to the idea that 1,024 megabytes equals one gigabyte, we’re fast coming upon the time when people will be referring to having “half a terabyte” storage, rather than 500 gigabytes. For now, however, the petabyte is safely relegated to university-owned supercomputers like those of Indiana University, The European Organization for Nuclear Research (CERN), and IBM’s Global Services, among others. We can only hope that by the time the home user is buying storage capacity by the petabyte, defragmentation programs have kept pace.