The reason is that you do not only use bytes to store numbers, but also to address memory bytes that store numbers (or even other addresses). With 1 Byte you have 256 possible addresses, so you can access 256 different bytes. Using only 200 bytes, for example, just because it is a rounder number would be a waste of address space.﻿

WHY ARE BYTES ALWAYS TALKED IN POWER OF 2

2^10 = 1KB,
2^20 = 1MB,
etc.
etc.Except, a byte is 8 bits so I do not understand why we are using powers of 2 as an explanation. To talk about Bits in powers of 2 I can completely understand but with Bytes, I am totally lost. Many textbooks / online resources talk about it in this way, what am I missing here?By the way, I understand 2^10 = 1024 which is approximately 10^3 = 1000. What I don't understand is why we justify the use prefixes and bytes using powers of 2.I'll ask the question you're really asking: Why don't we just use powers of 10?To which we'll respond: why should we use powers of 10? Because the lifeforms using the computers happen to have 10 fingers?Computers break everything down to 1s and 0s.1024 in binary = 10000000000 (2^10), which is a nice round number.1000 in binary = 1111101000 (not an even power of 2).If you are actually working with a computer at a low level (ie looking at the raw memory), it is much easier to think using numbers that get represented as round numbers in the way they are stored.<div dir="ltr">
 41.1k26</div><div>26 gold badges</div><div>130</div><div>130 silver badges</div><div>193</div><div>193 bronze badges</div><div itemprop="upvoteCount" data-value="4">
 4
 </div>From your question, I think that you understand about powers of two and measuring bytes. If not, the other answers explain that. Is your question is why not use bits rather than bytes since bits are truly binary? The reason that memory, disk space, etc is described in bytes rather than bits has to do with the word addressability of early computers. The bit, nibble and byte came about as workable amounts of memory in simple computers. The first computers had actual wires that linked the various bits together. 8-bit addressability was a significant step forward. Bytes instead of bits is just a historical convention. Networks measurements are in (mega) bits for similar historical reasons. Wikipedia has some interesting <a href="https://en.wikipedia.org/wiki/Byte" rel="nofollow" dir="ltr">details</a>. <div itemprop="upvoteCount" data-value="3">
 3
 </div>The reason is that you do not only use bytes to store numbers, but also to address memory bytes that store numbers (or even other addresses). With 1 Byte you have 256 possible addresses, so you can access 256 different bytes. Using only 200 bytes, for example, just because it is a rounder number would be a waste of address space.This example assumes 8 bit addresses for simplification, usually you have 64 bit addresses in modern PCs.By the way, in the context of hard drives, the amount of memory is often a round number, e.g. 1 TB, because they address memory space differently. Powers of 2 are used in most memory types, like RAM, flash drives/SSDs, cache memory. In these cases, they are sometimes rounded, e.g. 1024 KB as 1 MB.There are actually 2 different names for powers of 2 and powers of 10. Powers of ten are known as kilo-bytes, mega-bytes, giga-bytes, while powers of two are called kibi-bytes, mebi-bytes and gibi-bytes. Most people just use the former ones in both cases.<div itemprop="upvoteCount" data-value="-1">
 -1
 </div>I think the part that you are hung up on is the conversion from byte, to KB, to MB, etc. We all know the conversion, but let me clarify:1024 bytes is a kilobyte. 1024 kilobytes is a megabyte, etc. As far as the machines go, they don't care about this conversion! They just store it as x bytes. Honestly I'm not sure if it cares are bytes, and just deals with bits. While I'm not entirely sure, I think the 1024 rate is an arbitrary choice made by some human. It's close to 1000 which is used in the metric system. I thought the same thing as you did, like "this has nothing to do with binary!". As one of the other answers says, it's nothing more than "easy to work with".

computerscience

Computer Science

2^10 = 1KB, 2^20 = 1MB, etc. etc.

Except, a byte is 8 bits so I do not understand why we are using powers of 2 as an explanation. To talk about Bits in powers of 2 I can completely understand but with Bytes, I am totally lost. Many textbooks / online resources talk about it in this way, what am I missing here?

By the way, I understand 2^10 = 1024 which is approximately 10^3 = 1000. What I don't understand is why we justify the use prefixes and bytes using powers of 2.

I'll ask the question you're really asking: Why don't we just use powers of 10?

To which we'll respond: why should we use powers of 10? Because the lifeforms using the computers happen to have 10 fingers?

Computers break everything down to 1s and 0s.

1024 in binary = 10000000000 (2^10), which is a nice round number.

1000 in binary = 1111101000 (not an even power of 2).

If you are actually working with a computer at a low level (ie looking at the raw memory), it is much easier to think using numbers that get represented as round numbers in the way they are stored.

From your question, I think that you understand about powers of two and measuring bytes. If not, the other answers explain that.

Is your question is why not use bits rather than bytes since bits are truly binary?

The reason that memory, disk space, etc is described in bytes rather than bits has to do with the word addressability of early computers. The bit, nibble and byte came about as workable amounts of memory in simple computers. The first computers had actual wires that linked the various bits together. 8-bit addressability was a significant step forward.

Bytes instead of bits is just a historical convention. Networks measurements are in (mega) bits for similar historical reasons.

Wikipedia has some interesting <a href="https://en.wikipedia.org/wiki/Byte">details </a>.

The reason is that you do not only use bytes to store numbers, but also to address memory bytes that store numbers (or even other addresses). With 1 Byte you have 256 possible addresses, so you can access 256 different bytes. Using only 200 bytes, for example, just because it is a rounder number would be a waste of address space.

This example assumes 8 bit addresses for simplification, usually you have 64 bit addresses in modern PCs.

By the way, in the context of hard drives, the amount of memory is often a round number, e.g. 1 TB, because they address memory space differently. Powers of 2 are used in most memory types, like RAM, flash drives/SSDs, cache memory. In these cases, they are sometimes rounded, e.g. 1024 KB as 1 MB.

There are actually 2 different names for powers of 2 and powers of 10. Powers of ten are known as kilo-bytes, mega-bytes, giga-bytes, while powers of two are called kibi-bytes, mebi-bytes and gibi-bytes. Most people just use the former ones in both cases.

I think the part that you are hung up on is the conversion from byte, to KB, to MB, etc. We all know the conversion, but let me clarify:

1024 bytes is a kilobyte. 1024 kilobytes is a megabyte, etc.

As far as the machines go, they don't care about this conversion! They just store it as x bytes. Honestly I'm not sure if it cares are bytes, and just deals with bits.

While I'm not entirely sure, I think the 1024 rate is an arbitrary choice made by some human. It's close to 1000 which is used in the metric system. I thought the same thing as you did, like "this has nothing to do with binary!". As one of the other answers says, it's nothing more than "easy to work with".

Why are Bytes talked about in powers of 2?

WHY ARE BYTES ALWAYS TALKED IN POWER OF 2

candid kumar's ideas are part of this journey:

Related collections

Similar ideas