Discovering Computer Science

CHAPTER 6

Text, documents, and DNA

So, here’s what I can say: the Library of Congress has more than 3 petabytes of digital collections. What else I can say with all certainty is that by the time you read this, all the numbers — counts and amount of storage — will have changed.

Leslie Johnston, former Chief of Repository Development, Library of CongressBlog post (2012)

The roughly 2000 sequencing instruments in labs and hospitals around the world can collectively sequence 15 quadrillion nucleotides per year, which equals about 15 petabytes of compressed genetic data. A petabyte is 2⁵⁰ bytes, or in round numbers, 1000 terabytes. To put this into perspective, if you were to write this data onto standard DVDs, the resulting stack would be more ...