We discovered that a little more technical background is required at this point. Inside a typical computer’s memory, the thing that remembers if a given bit should be a 1 or a 0 is a capacitor. This is a component on a chip (typically) that is capable of holding a small amount of electrical charge. Charge up a cell’s capacitor and it represents a 1. Uncharged, it represents a 0. The memory’s capacitors are so small that they each require only about 40,000 electrons to charge up. That’s a really small amount: Some 5.7 x 1018 electrons flow through a 100-watt lightbulb every second.
Now let’s look at a typical e-mail, such as some text and a Microsoft Word attachment—like when we sent draft versions of this article home to ponder the problem overnight. Such an e-mail contains about 50 kilobytes. Because there are 8 bits in a byte and 1,024 bytes in a kilobyte, that e-mail is composed of 409,600 bits. Not all of those bits are going to be 1s—that would be a pretty boring e-mail message! On average, about half of the bits will be 1s and half 0s, so that’s 204,800 1s that have to be stored, requiring a total of about 8 billion electrons. One electron weighs 2 x 10-30 pound, so a 50-kilobyte e-mail weighs about two ten-thousandths of a quadrillionth of an ounce, about the weight of 21,000 lead atoms. That may sound like a lot, but in fact it’s a tiny amount—an ounce of lead contains about 82 million quadrillion atoms.
But that’s just one e-mail. How much information—all the Web pages, instant messages, video streams, and everything else you can imagine—passes through the Internet as a whole? Not an easy number to track down, but finally we got our answer from Clifford Holliday, author of Internet Growth 2006 (published by the telecommunications consultancy Information Gatekeepers). He estimates the total amount of Internet traffic by looking at the activity of end-user connections, such as dial-up modem lines, DSL, and fiber-optic connections. Broadband connections to homes and businesses, like DSL and cable modems, are responsible for generating most of the load, which also goes a long way toward Holliday’s discovery that 75 percent of all traffic on the Internet is due to file sharing, with 59 percent of that file sharing attributed to people swapping video files. Music tracks account for 33 percent of the file-sharing traffic. E-mail, it turns out, accounts for just 9 percent of the total traffic. And that total is... a staggering 40 petabytes, or 40 x 1015 bytes: a 4 followed by 16 zeros.
Taking Holliday’s 40-petabyte figure and plugging it into the same formula that we worked out for our 50-kilobyte e-mail results in a grand total of 1.3 x 10-8 pound. At last, after much scribbling (and perhaps a little cursing), we had our answer: The weight of the Internet adds up to just about 0.2 millionths of an ounce.
Love letters, business contracts, holiday snaps, spam, petitions, emergency bulletins, pornography, wedding announcements, TV shows, news articles, vacation plans, home movies, press releases, celebrity Web pages, home movies, secrets of every stripe, military orders, music, newsletters, confessions, congratulations—every shade and aspect of human life encoded as 1s and 0s. Taken together, they weigh roughly the same as the smallest possible sand grain, one measuring just two-thousandths of an inch across.
William Blake’s famous poem Auguries of Innocence (1803) begins, “To see a world in a grain of sand....” He was being more prophetic than he could have ever known.