Weekly Classic Computer Trivia Question (20141205)

Johnny Billquist bqt at update.uu.se
Sat Dec 6 12:54:18 CST 2014

On 2014-12-06 19:48, Johnny Billquist wrote:
> On 2014-12-06 15:02, Peter Corlett wrote:
>> Consider also the infamous 1.44MB disk.  That number comes from 1440 *
>> 1024, so
>> apparently a megabyte is *also* 1,024,000 bytes.  If we can
>> humpty-dumpty it
>> and pluck numbers out of the air, why not just call a megabyte
>> 3,141,592 bytes?
> Actually, the 1.44MB floppy holds 1,474,560 bytes.
> 512 bytes per sector, 18 sectors per track, 80 tracks per side, and two
> sides... Where did you pull the 1440*1024 from???

I should actually do my math before commenting. :-)
It just happens, that by a funny accident, 1440*1024 is actually 1,474,560.

But still. The actual size of the floppy wasn't decided because you 
pulled out 1440*1024, but because of the format of the darn thing. 
1.44MB is just the closest "nice" number you can come up with after the 
fact as a way to talk about the capacity of the thing.

It is not an exact number, but they seldom are, when we talk about 
storage. People like to round things off, to make it easier to talk about.


Johnny Billquist                  || "I'm on a bus
                                   ||  on a psychedelic trip
email: bqt at softjar.se             ||  Reading murder books
pdp is alive!                     ||  tryin' to stay hip" - B. Idol

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