How many megabytes are in a gigabyte?

(5) On April 19, 2012 at 1:29 am BLOK111333666444 [0] said:

1 Byte 8 bits

1 KB 1024 bytes

1 MB 1024 KB

1 GB 1024 MB

1 TB 1024 GB

1 PetaByte 1024 TB

1 Exabyte 1024 Petabyte

1 Zattabyte 1024 Exabyte

1 Yottabyte 1024 Exa byte

Source: http://www.chaaban.info/2006/11/02/what-comes-after-the-terabyte/

How's That

(4) On November 27, 2011 at 7:29 am Trims [94] said:

Some historial reference:

All modern computers use binary as their basis for calculation. That is, computers use a Base 2 system, instead of the Base 10 systems humans have found convenient.

As humans are used to dealing in quantities of things in units of 10, when computing was in its infancy, common usage was to take the SI standard prefixes for various powers of 10 (kilo-, mega-, giga-, etc.) and apply them as powers to the standard Base 2 of the computing world. It helped that 2^10 is very close to 10^3.

So, for most of the computing industry's life, internal quantification of amounts has assumed that the prefixes indicate a power of 2^10. Prior to about 2000, virtually ANY discussion of any quantity inside a computer (including things that weren't technically tied to a Base 2 system, such as clock frequency) was understood to be using 2^10 for each SI prefix. Thus, Mega implied 2^10 amounts of Kilo, or 2^20.

A fly in this ointment was Networking, which has always used the electrical standard where SI prefixes mean exactly Base 10 measurements. So, discussions of frequency and such in a network setting always assumed Base 10 amounts for Kilo, Mega, etc.

As computers became commonplace, and as most consumers were not aware of the differences in terminology between the computing definition of the SI prefixes as the original use of them, around 2000 the disk drive industry decided to standardize their marketing material to use the original Base 10 meaning. Internally, disk drives still measuring things in Base 2, but all marketing and technical datasheets now use Base 10 for quantifying the capacity of a device.

This caused a huge amount of confusion in computing, as various industries were now using Kilo, etc. to mean completely different things. An SI panel was set up to try to fix this, and came up with a whole new terminology to use for the Base 2 system: they merely appended an "i" to end of the normal Base 10 SI prefixes. Thus, "Ki" means "Kibi", or 2^10, while "K" is "Kilo" and means 1000.

Most computer industry insiders completely ignored this outside attempt to redefine well-known usage, and pretty much all software code still uses the old 2^10 definitions for "Kilo" et al, and is unlikely to change.

Thus, the user-visible quantities show are in Base 2 with the old SI prefixes, not the new ones.

For instance: Marketing and technical datasheets for disk drives use Base 10, so a 100GB drive has 100,000,000,000 bytes, or 10^11 bits. Sticking that drive into a computer, and the OS then calculates what it thinks the sizes in its Base 2 system, and arrives at about 93.13 GB which is what is shown to the end-user when the OS is querried for the human-readable size.

Frankly, I'm an industry old-timer, and the Kibi, et al stuff is stupid, silly, and will never be used in any serious discussion. Those with enough technical knowledge will stick with tradition, and, in fact, actively mark any person using Kibi-, et al as a marketdroid, and ignore them.

(3) On September 14, 2011 at 10:42 am Halwits2011 [1] said:

1 gigabyte = 1024 megabytes

(2) On April 23, 2010 at 6:40 am Bobmacans [0] said:

1024 MB is equal to 1 GB

(1) On September 2, 2009 at 6:13 pm LeviticusMN [172] said:

Note: LeviticusMN changed "How many MB are in a GB?" to "How many megabytes are in a gigabyte?".

See the Discussion for "How many MB are in a GB?"

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