The MST Reader is a series of overviews of interesting and timely topics that affect our world.
The MST Reader: Information in Motion
In 1985, global Internet traffic — the total of all Internet traffic, from everyone to everyone, was 33 gigabytes per month. By 1995, at the dawn of the World Wide Web and the commercial Internet, that had grown to 150,000 gigabytes per month. By 2005 that had become 1.8 exabytes per month, and by 2015 it was 52 exabytes per month. In 2019, before the pandemic surge, monthly traffic exceeded 166 exabytes. [source: Cisco]
These numbers are almost impossible to make sense of, but let’s try!
Let’s start small first. A bit is a single unit of digital information — a zero or a one.
8 bits = 1 byte (a single character of text usually requires 1 byte)
1024 bytes = 1 kilobyte
1024 kilobytes= 1 megabyte
1024 megabytes = 1 gigabyte
1024 gigabytes = 1 terabyte
1024 terabytes = 1 petabyte
1024 petabytes = 1 exabyte
1024 exabytes = 1 zettabyte
One kilobyte can hold roughly a half a page of normal text, so a page of text is about 2 kilobytes. That means a megabyte is approximately 500 pages, and a gigabyte roughly 500,000 pages, which is a very long book; or, if we consider a book to be 300 pages, then it is more than 1600 books.
That means a terabyte is 1.7 million books, a petabyte is 1.7 billion books, and our analogy has lost meaning already since Google estimates there were only 130 million books in the world as of 2010.
One estimate is that 5 exabytes would be more than all the words ever spoken by human beings.
It might make more sense to think in terms of video, since somewhere around 75% of Internet traffic is video. Old-school broadcast television was analog, not digital, but it converts to roughly a 480i resolution, which would stream at about 700 megabytes per hour, depending on compression. HD-quality video streams at between .9 gigabytes and 3 gigabytes per hour, and a 4K stream will use about 7.2 gigabytes per hour.
So, if a terabyte is about 142 hours of 4K video, then a petabyte is about 142,000 hours, and an exabyte is 142 million hours, or 16,000 years of 4K video. That means the average monthly Internet traffic in 2019 was equivalent to about 2.6 million years of 4K video.
In 2017, YouTube alone passed 1 billion hours a day of videos viewed. That is to say, the people of Earth collectively spent over one billion hours every day, watching YouTube videos. That is the equivalent of 140,000 years of YouTube videos watched every day. (A podcast called “Rabbit Hole” explores the effects this is having on us.)
It’s a boggling amount of data moving back and forth, which we now take for granted. Imagine, in contrast, the bitrate of a radio broadcast, or a daily newspaper, or a letter, or the human voice. Once, these were the standards for data transmission in the world.