Date: Thu, 14 Jan 2010 23:35:15 -0600 (CST) From: Mark Jacobson To: 810-023-01-spring@uni.edu Subject: Paper folded 50 times is 71 million miles thick... Hi 023 students, Forgot to mention this in review of today's class exercise: ---------------- Paper folded 50 times would be 71 million miles thick or tall... ---------------- See the class web page at: http://www.cs.uni.edu/~jacobson/23/ Folding the paper 10 times would be 1K or 1 KB or 1024 sheets 20 times would be 1M or 1 MB sheets 30 1G 1 GB or 1 gigabyte sheets 40 1T 1 TB or 1 terabyte sheets http://en.wikipedia.org/wiki/Terabyte 1,125,899,906,842,624 PB, TB, GB, MB, KB, B where B = bytes KB = kilobytes MB = megabytes GB = gigabytes TB = terabytes and PB = petabytes 50 1,125,899,906,842,624 is equal to 1 petabyte or 1 PB = 2 = 2 ^ 50 1 petabyte pile of sheets of paper would almost reach the sun from the earth here, though stacking it that high would be tricky. ---------------- Paper folded 50 times would be 71 million miles thick or tall... ---------------- Will college students and you 25 years from now be using PCs and Macs with petabytes of hard drive capacity and terabytes of RAM memory capacity? Moore's Law = every 18 months ... http://en.wikipedia.org/wiki/Moore%27s_law Mark