Mega & Giga?

[D]

The terms mega meaning 1,000,000
and giga meaning 1,000,000,000
come from what system? I don't seem to find them
in the metric listings?

[Alf P. Steinbach]

Post by D
The terms mega meaning 1,000,000
and giga meaning 1,000,000,000
come from what system? I don't seem to find them
in the metric listings?

These are the official SI units.

For memory you have (since late 1990's) KiB (yes, uppercase K), MiB,
GiB etc., which are powers of 2.

Traditionally of course, and especially in Windows programming, KB
means 2^10 bytes (and uppercase K isn't SI standard so it couldn't
very well mean 1000 bytes, but MB, GB, TB and PB are likewise).

[D. Keletsekis]

Post by D
The terms mega meaning 1,000,000
and giga meaning 1,000,000,000
come from what system? I don't seem to find them
in the metric listings?

I don't think they come from any particular system, nor are they used
in computing only - you have for example megawatts & gigawatts in
electricity and other places too.

They're from Greek:
mega - means great (like in megalomania)
giga - means gigantic (like in giant)
tera - means monstrous

I don't remember whats after tera, but it must be pretty frightening:)

Dimitris
www.Gui4Cli.com

[r***@pen_fact.com]

Post by D
The terms mega meaning 1,000,000
and giga meaning 1,000,000,000
come from what system? I don't seem to find them
in the metric listings?

I think this is relevant:
http://www.bcpl.net/~martylog/metric.html
I found it by going to www.firstgov.gov and searching for
metric prefixes


I also used google (http://groups.google.com/advanced_group_search) to
look up
milli micro kilo giga
That led me to the following 4 April 1999 contribution from Ford to a
thread called "Greek and Latin roots (was Re: Flying with the OP)" in
rec.arts.sf.written.robert-jordan:
"It's my understanding that we use Latin prefixes for things smaller
than 1(deci-, milli-, micro-, etc.) and Greek prefixes for things
greater than 1(deka-, kilo-, mega-, etc.)... And I've looked all these
up in the dictionary, and the roots are labeled as Lat. for deci,
milli and micro, and Gk. for deka, kilo and mega. I'm sure the trend
continues for tera, giga, pico, nano, hecto, centi, and any other
roots you care to check.
(I'm lazy; sue me.)"
This confirms my recollection about the Greek/Roman distinction.


(Along the way, I got a reminder about the wild diversity of
newsgroups. Some I want nothing to do with. Some I'm glad to dip into
via google.)

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[Victor Bazarov]

Post by r***@pen_fact.com

Post by D
The terms mega meaning 1,000,000
and giga meaning 1,000,000,000
come from what system? I don't seem to find them
in the metric listings?

http://www.bcpl.net/~martylog/metric.html
I found it by going to www.firstgov.gov and searching for
metric prefixes

It contains an obvious error. 2^30 is called "Tera Binary", and it should
be obviously, "GigaBinary". The names have to be shifted in the table at
the end of the page. "TeraBinary" is 2^40. "PetaBinary" is 2^50, and
"ExaBinary" is 2^60.

Post by r***@pen_fact.com
[...]

Victor

P.S. I am CC'ing this to the site maintainer, Leonard S. Kramer.