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Hackers pretty much think in binary. This is why, as Neal Stephenson points out in Snow Crash, they have a fetish for powers of two. That is to say, hackers like numbers such as 2x2x2 and 2x2x2x2, which is why CPUs are often 8-bit or 16-bit, and why digital storage space is measured in multiples of 1024 bytes (2 to the power of 10) instead of multiples of 1000 bytes.

Digital high definition videos are available in two main sizes: 720p and 1080p. The p means it's progressive, meaning that each and every line of the image is updated with every frame, and the number is simply the number of horizontal lines in each image.

As a hacker, I was slightly confused at first as to why the people who designed the high definition format went with the seemingly arbitrary number 1080 as opposed to the more familiar hacker's preference of 1024. I tried to find any important properties of 1080, and its Babylonian root soon became clear. I can see now that it's not arbitrary at all.

The ancient Babylonians didn't think in binary. They thought in fractions. They loved numbers which had as many divisors as possible. In other words, they loved whole numbers that were divisible by as many other whole numbers as possible. The antithesis of prime numbers, if you will, as prime numbers are divisible only by 1 and themselves.

This is why they loved numbers like 60, which has 12 divisors. In other words, 60 is divisible by 12 whole numbers, namely 1, 2, 3, 4, 5, 6, 10, 12, 15, 20, 30, and 60. Even better is 360, which is 60 multiplied by 6. 360 has 24 divisors: 1, 2, 3, 4, 5, 6, 8, 9, 10, 12, 15, 18, 20, 24, 30, 36, 40, 45, 60, 72, 90, 120, 180, and 360.

If the numbers 60 and 360 seem strangely familiar, that's because they remain in our culture to this day. There are 60 seconds in a minute, 60 minutes in an hour, and 24 hours in a day (or two lots of 12 hours, depending on how you look at it). I can only imagine these people were rather irked to discover there were 365 1/4 days in a year, not a perfect 360.

There are 360 degrees in a circle. This is completely arbitrary -- you can split up a circle into as many slices as you wish, but the Babylonians loved the number 360 and it's stuck ever since, although we're finally starting to measure circles in radians instead. Earth is pretty much a sphere (technically, it's an oblate spheroid), so your position on its surface -- your latitude and longitude -- can be measured in degrees.

Remember that Earth rotates once per day, by the very definition of what a day is. In other words, Earth rotates 360 degrees every day. So our measurements of both time and space are based on Babylonian mathematics.

Skipping ahead a few millenia, back to the present day (2009 at the time of writing), we've got high definition videos popping up in shops all over the Western world. So high, in fact, that a lot of televisions aren't big enough to display their images, so they often need to be scaled down to fit on the screen. With most numbers of lines, the formula to work out when to show a line and when to skip it would be unnecessarily complicated and possibly cause slight distorting of the image.

However, 720 and 1080 are double and triple 360, so they have a lot of divisors. Just by removing every second line, every third line, two out of every three, and so on, 1080-line images can be scaled down to an impressive range of smaller sizes smoothly and efficiently. I'm sure the ancient Babylonians would have approved.

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