howtogeek — 2013-04-16T16:03:01-04:00 — #1
Originally published at: http://www.howtogeek.com/149225/why-do-computers-count-from-zero/
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xhi — 2013-04-16T18:41:58-04:00 — #2
Hmmm, I think a simpler answer is that if you do not start counting at 0 you have a real hard time arriving at -1. Also what does one call it if all bits are off? Also if you do not start at 0 a binary system would become a unary system, an octal system would become a septal system. I can not imagine why this is a question that needs an answer.
geek — 2013-04-16T18:45:23-04:00 — #3
Mostly because there are a lot of people that don't understand some of the underlying principles of computing, so they don't understand why we count from 1, but computers count from zero.
xhi — 2013-04-16T18:58:09-04:00 — #4
One can not count without a some kind of concept whether they realize it or not. It is not only computers that start at zero. If one is counting something and there is none of them the answer is none, nil nada, zero. As I said as soon as negative numbers are introduced, which was long before computers zero was a concept that had to be understood.
raphoenix — 2013-04-16T19:08:34-04:00 — #5
philip — 2013-04-17T16:33:57-04:00 — #6
It boils down to efficiency and information theory. A single bit can be either a 0 or 1. If you have a 4-bit value, you can represent 16 possible states with it, from 0000 (zero) to 1111 (15). If you start counting at 0001, you lose one of those states. This kind of thing sounds foolish when our phones have many gigabytes of memory, but this all started when computers counted memory in bytes and kilobytes.
andrewrobert7 — 2013-04-17T19:22:21-04:00 — #7
Yep, it was an early concept that just stuck.
whs — 2013-04-17T19:43:44-04:00 — #8
Yeah, I remember that. One of the early machines I worked on had 1.4KB of RAM (called core storage in those days as opposed to the earlier systems that had drum storage). And when it was upgraded to 4KB, we felt like kings.
xhi — 2013-04-17T21:22:44-04:00 — #9
My first computer that I owned was a PDP11-01. It had 28K of memory expandable to a maximum of 32k. Cost $9000 in 1970. In today's dollars $48,976.47
raphoenix — 2013-04-17T21:31:49-04:00 — #10
One of the only Two OEM machines I have ever owned was one the first IBM Personal Computers.
Fully loaded with accessories of that period, the machine cost me $8000 dollars.
Wonder what our old machines would cost in Today's Dollars ????
xhi — 2013-04-17T21:40:27-04:00 — #11
Just google "What is the value of a 19xx dollar in todays dollars?"
raphoenix — 2013-04-17T21:54:09-04:00 — #12
whs — 2013-04-17T21:59:22-04:00 — #13
I wonder on which shopping basket they base that inflation rate. I calculated @20 in 1964 and it comes up with appr. $150 today.
I remember in 1962 when we spent $20 in the supermarket my Olds 88 trunk was full of brown bags. If I spend $150 today, my Mercury trunk is not at all full. And that trunk is smaller than the Olds trunk. And gas was 26 cents/gallon.
There must be a lot of technology items in the shopping cart that they use as a base because those really got cheaper.
raphoenix — 2013-04-17T22:05:10-04:00 — #14
I saw a number of ways to calculate the difference including the use of Calculus but just chose the Simple App.
geek — 2014-07-11T14:26:38-04:00 — #16
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