Bitcoin is limited to 21 million

1. It is recommended not to participate in investment,

this kind of virtual currency is not a digital currency recognized by the central bank,

it is not protected by law,

the corresponding platform may collapse or run away at any time.

2. One of the controversial attributes of bitcoin is its fixed supply. At present, 25 new bitcoins are proced every 10 minutes, and the number is halved every four years. Overall, there won't be more than 21 million bitcoins & gt;. On the other hand, each bitcoin can be divided into 100 million shares (each is called 1 "cong"), if one cent is enough to buy a car, it will be troublesome to trade in US dollars, but even if bitcoin rises to the level of US dollars assumed above & gt; We will not encounter such problems. Therefore, in short, the total number of monetary units that will always exist is 2100 billion, that is 2100 trillion, or 250.899. In the square of choosing this value & gt; In fact, Nakamoto is much luckier or smarter than most people realize. First of all, this number is far less than 264-1, which is the largest integer that can be stored in the form of standard integer in a computer. If it exceeds that value, & gt; The value will return to zero like a odometer
secondly, however, there is a smaller threshold for the total number of "smart": the largest possible integer that can be represented in floating-point format. Integers are not the only numbers that computers can store; To deal with decimals, computers & gt; Use a format for floating point representation. Floating point notation is essentially a binary version of scientific notation. For example, here is a value you will encounter when you study physics:
mass of the earth: 5.972 1024 kg
mass of the sun: 1.989 1030 kg
speed of light: 2.998 108 M / s
light year: 9.460 1015 m
mass of proton: 1.672 10-27 kg
Planck length: 1.616 10-35 m
we can notice that, How does scientific notation allow you to represent all of these values with reasonable accuracy, even though they vary greatly in size. Floating point notation is essentially a binary scientific notation; When you store numbers & gt; When the word is 9.625, what your computer stores is "1.001101
* 1011" (in other words, it stores 0100000000100011
& gt; This is the same thing with high-precision sequence form). In this high-precision form, the coefficient (that is, the part that is not the exponent) has 52 bits. This means high precision (more refined & gt; Double precision floating point number is enough to store up to 253 numbers, but it can't be any higher. If it exceeds 253, you have to start cutting off the numbers at the end. Bitcoin's 250.9, the total number of "smart" in the form of index, is just & gt; OK, below this maximum
if we have integers, why should we care about floating-point values? Because more high-level programming languages (such as JavaScript) do not open low-level "floating point" and "integer representation", but only provide "number" representation for programmers; Concepts
– of course, in floating-point form. If Nakamoto chose 210 million instead of 21 million at that time, bitcoin programming in many languages would be much more troublesome than it is now
note that Stefan Thomas unfortunately didn't notice this in time when he wrote bitcoinjs, so that the library used a special "big number big
number" object instead of an ordinary number to store the tutorial output value; My own bifurcated bitcoin JS (along with other improvements) uses ordinary numbers.

3. The upper limit of bitcoin is not the exact figure of 21 million. 21 million is calculated according to the mining rules
in the first four years, 50 pieces were g out every ten minutes: 50 * 6 * 24 * (365 * 4 + 1) = 10519200 pieces
in the second four years, 25 pieces were g out every ten minutes: 25 * 6 * 24 * (365 * 4 + 1) = 5259600 pieces
according to the sum formula of infinite equal ratio sequence, the final total amount is infinitely close to 21038400 pieces (10519200 * 2)
as long as the mining rules are not changed, the number of bitcoins will never exceed 21038400

4. There is an upper limit to the number of bitcoins, mainly because there is an upper limit to the solution set of the algorithms involved in the program. The algorithm is very complex. In theory, no computer has such powerful computing power that it can solve 51% of the solution set, that is, no one can control bitcoin

so far, the number of bitcoins has reached 12 million. To be exact, the maximum number of bitcoins should be 2099990000, but in fact, the current mining (mining) process is quite difficult - no less difficult than connecting 1000 home computers, and then continuously calculating for a month, it is not possible to dig out a bitcoin

I hope I can help you.

5. The upper limit is 21 million. The solution to this problem is divisible. That is to say, you can take 0.0001 BTCs or 0.002 BTCs. Because of its divisibility, you don't have to worry about it. You can be sure that there will be less and less bitcoins in the end. Because of the loss, there will be more and more missing bitcoins for various reasons

6. Due to the decentralized programming of the bitcoin system, only 25 bitcoins can be obtained every 10 minutes. By 2140, the maximum number of bitcoins in circulation will reach 21 million. In other words, bitcoin system is able to achieve self-sufficiency, resist inflation through coding, and prevent others from destroying these codes.

7. At that time, Nakamoto set a maximum of 21 million rules

9. You know the police station? Just look around the police station. It's almost in the lower left corner of the police station. The icon is what they call three villains with different movements