From The Numbers Guy at wsj.com:
The latest information about information overload is a lot to handle.
Wielding numbers that stretched to 20 or more digits, researchers recently reported on the world's massive ability to store, communicate and compute information. All three have grown at annual rates of at least 23% since 1986, according to a study published this month in Science.
For data engineers, this might seem like cause for celebrating humanity's expanding universe of information. For the rest of us, it is another reminder that information is piling up at overwhelming rates.
But the digital avalanche isn't as massive as those numbers suggest. Much of the growth reflects the surge in high-resolution video and photos. In addition, while there is much more information available, each piece is being consumed, on average, by far fewer people than in the past.
Also, heavy Internet users—think downloaders of music and movies, or digital-photo fiends—are skewing the numbers. The average person doesn't have a high-speed line, let alone the ability to read six newspapers per day.
Not all forms of information grew at the same pace, the Science study reveals. The amount of data stored in books roughly doubled between 1986 and 2007, a period during which the world population increased by about a third. The increase in newsprint was a relatively manageable 91%, while available storage—a barometer researchers used to estimate the quantity of information—in audio cassettes, vinyl records and photo negatives all declined. And nearly half the overall growth came from rapid improvements in hard-drive technology, making it possible to store high-resolution videos, photos and videogames as well as digital music.
Studies looking at the information glut do generally agree that there has been an enormous upsurge in information.
The Science study—which involved compiling disparate studies of the number of various devices and their capacity—found that in 2007, humanity was able to store 295 exabytes of information. That's 295 billion gigabytes, or about 500 million times the capacity of a typical desktop computer.
Read more here.