<p>Bitcoin (capital B) is the name of a currency, a technology, and a movement. A bitcoin (small b) is a unit of this currency.</p>

<p>Example: "After hearing about Bitcoin, I've installed a Bitcoin client and bought 3 bitcoins."</p>

CC BY-SA 3.0
2014-01-21T19:40:29.120Z
2014-01-21T19:40:29.120Z
Meni Rosenfeld
<p>From <a href="https://en.bitcoin.it/wiki/Introduction" rel="noreferrer">Introduction</a> on the Bitcoin wiki:</p>
<blockquote>
<h1>Capitalization / Nomenclature</h1>
<p>Since Bitcoin is both a currency and a protocol, capitalization can be confusing. Accepted practice is to use Bitcoin (singular with an upper case letter B) to label the protocol, software, and community, and bitcoins (with a lower case b) to label units of the currency.</p>
</blockquote>
<p>So, the accepted usage in your example would be &quot;3 bitcoin&quot; and the &quot;Bitcoin protocol&quot;.</p>

CC BY-SA 3.0
2014-03-25T08:54:42.443Z
So "add the bitcoin amount" with small b is correct as we talk about the units of the currency? Thanks.
Cimm
CC BY-SA 3.0
2014-06-02T09:20:36.213Z
@Greg, So would we say "I have a bitcoin address" or "I have a Bitcoin address"?
Pacerier
CC BY-SA 3.0
2014-06-02T16:09:52.730Z
@Pacerier: According to the above, that would be "Bitcoin address".
Greg Hewgill
CC BY-SA 3.0
2014-01-21T19:40:20.960Z
2014-01-21T19:40:20.960Z
2020-06-16T11:10:03.350Z
Greg Hewgill
<p>I'm still unsure when to use <code>Bitcoin</code> and when <code>bitcoin</code> is more appropriate. Did anyone define when to use the word Bitcoin with a capital <code>B</code>? Is one used to talk about the currency as in "3 Bitcoin" and the other for the "bitcoin protocol"?</p>

<protocol><currencies><legal>
Correct use of the word Bitcoin
Cimm
# Correct use of the word Bitcoin

(Asked by: username_0 on 2014-01-21)

I'm still unsure when to use `Bitcoin` and when `bitcoin` is more appropriate. Did anyone define when to use the word Bitcoin with a capital `B`? Is one used to talk about the currency as in "3 Bitcoin" and the other for the "bitcoin protocol"?

**Tags:** protocol, currencies, legal


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## 2 answers

### Answer by username_2 on 2014-01-21. Score: 7 | Accepted answer

From [Introduction](https://en.bitcoin.it/wiki/Introduction) on the Bitcoin wiki:

> # Capitalization / Nomenclature
>
> Since Bitcoin is both a currency and a protocol, capitalization can be confusing. Accepted practice is to use Bitcoin (singular with an upper case letter B) to label the protocol, software, and community, and bitcoins (with a lower case b) to label units of the currency.

So, the accepted usage in your example would be "3 bitcoin" and the "Bitcoin protocol".

> **Comments:**
> **username_0**: So "add the bitcoin amount" with small b is correct as we talk about the units of the currency? Thanks.  
> **username_3**: @username_2, So would we say "I have a bitcoin address" or "I have a Bitcoin address"?  
> **username_2**: @username_3: According to the above, that would be "Bitcoin address".  

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### Answer by username_1 on 2014-01-21. Score: 4

Bitcoin (capital B) is the name of a currency, a technology, and a movement. A bitcoin (small b) is a unit of this currency.

Example: "After hearing about Bitcoin, I've installed a Bitcoin client and bought 3 bitcoins."


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