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How to buy Used pinball Machines
In recent years, pinball machines have become increasingly popular among collectors. There are many different types of used pinball machines out there, including vintage models, modern games, and even video-pinball machines. If you’re looking to buy a Used pinball machine, here are some tips to keep in mind.
- Know Your Budget
The first thing that you need to do when buying a used pinball machine is determine your budget. You can spend anywhere from $5000 to 32000 on a single game. The average price of a new pinball machine is around $16000. However, if you want to save money, you can find good deals at garage sales or thrift stores.
- Find Out What’s Missing
Before you start shopping for a used pinball machine, it’s important to know what’s missing. For example, if the machine has been broken into, then you’ll need to replace all of the parts before selling it. Also, make sure that the machine works properly. If the machine doesn’t work, then you won’t be able to sell it.
- Look At The Parts
Once you’ve determined how much you can afford to pay for a used pinball game, then you should look at the parts. The most common part that people will want to purchase is the playfield (the actual playing surface). This is because the playfield is where the action takes place. Other parts that people may want to consider purchasing include the backbox (a metal box behind the playfield), the speaker system, and the flippers.
Types of Pinball Machines
There are three basic types of pinball machines: upright, drop-down, and flipper.
Upright pinballs are the original model, while drop-down pinballs are slightly smaller and easier to maneuver.
Flippers pinball are larger and require less skill to operate. The most popular type is the upright pinball machine, which has a large glass top with a steel frame that holds the game pieces in place. A player can play this type of pinball by sitting on a small stool or standing up.
The Green Solution® • Cannabis can be found in various forms, and the health benefits of cannabis is ever growing, here Tara Leo of CaliExtractions gives us an insight regarding the diverse benefits of the plant.
Cannabis contains CBD which is a chemical that impacts the brain, making it function better without giving it a high along with THC which has pain relieving properties. Both substances can be extracted and enhanced for use through short path distillation. Users can get the following health benefits of cannabis:
Relief of chronic pain
There are hundreds of chemical compounds in cannabis, many of which are cannabinoids. Cannabinoids have been linked to providing relief of chronic pain due to their chemical makeup. Which is why cannabis’ by-product such as medical cannabis is commonly used for chronic pain relief.
Improves lung capacity
Unlike smoking cigarettes, when smoking cannabis in the form of cannabis your lungs aren’t harmed. In fact, a study found that cannabis actually helps increase the capacity of the lungs rather than cause any harm to it.
Help lose weight
If you look around, you will notice that the avid cannabis user is usually not overweight. That is because cannabis is linked to aiding your body in regulating insulin while managing caloric intake efficiently.
Regulate and prevent diabetes
With its impact on insulin, it only makes sense that cannabis can help regulate and prevent diabetes. Research conducted by the American Alliance for Medical Cannabis (AAMC) has linked cannabis to stabilise blood sugars, lower blood pressure, and improve blood circulation.
One of the biggest medical benefits of cannabis is its link to fighting cancer. There is a good amount of evidence that shows cannabinoids can help fight cancer or at least certain types of it.
Helps treat depression
Depression is fairly widespread without most people even knowing they have it. The endocannabinoid compounds in cannabis can help in stabilising moods which can ease depression.
Shows promise in autism treatment
Cannabis is known to calm users down and control their mood. It can help children with autism that experience frequent violent mood swings control it.
Research conducted on CBD has shown that it can help control seizures. There are ongoing studies to determine the effect cannabis has on individuals with epilepsy.
Cannabidiol has been linked to helping heal broken bones, quickening the process. According to Bone Research Laboratory in Tel Aviv, it also helps strengthen the bone in the process of healing. This makes it tougher for the bone to break in the future.
Helps with ADHD/ADD
Individuals with ADHD and ADD have trouble focusing on tasks at hand. They tend to have problems with cognitive performance and concentration. Cannabis has shown promise in promoting focus and helping individuals with ADHD/ADD. It is also considered a safer alternative to Adderall and Ritalin.
Treatment for glaucoma
Glaucoma leads to additional pressure on the eyeball which is painful for individuals with the disorder. Cannabis can help reduce the pressure applied on the eyeball providing some temporary relief to individuals with glaucoma.
While Cannabis is commonly known to cause anxiety, there is a way around that. Taken in monitored dosage and in the proper way, cannabis can help alleviate anxiety and calm users down.
Slow development of Alzheimer’s disease
Alzheimer’s disease is one of many that is caused by cognitive degeneration. As we age, cognitive degeneration is almost unavoidable. Cannabis’s endocannabinoid contains anti-inflammatories that fight the brain inflammation that leads to Alzheimer’s disease.
Deal with pain linked to arthritis
Cannabis is now commonly found as creams and balms which are used by individuals that have arthritis. Both THC and CBD help sufferers deal with the pain.
Helps with PTSD symptoms
PTSD doesn’t just affect veterans but any individual that goes through a trauma. As cannabis is legalised the impact it has on helping treat individuals with PTSD is being studied. Cannabis helps control the fight or flight response, preventing it from going into overdrive.
Helps provide relief to individuals with multiple sclerosis
Multiple sclerosis can be painful, and cannabis is known to provide relief for it. Multiple sclerosis leads to painful muscle contractions and cannabis can help reduce that pain.
Reduces side effects linked to hepatitis C and increase the effectiveness of treatment
The treatment for hepatitis C has numerous side effects that include nausea, fatigue, depression, and muscle aches. These can last for months for some hepatitis C sufferers. Cannabis can help reduce the side effects caused by the treatment while making it more effective at the same time.
Treats inflammatory bowel diseases
Individuals with Crohn’s disease or ulcerative colitis can find some relief with the use of cannabis. THC and cannabidiol are known to help enhance immune response while also interact with cells that play a vital role in the functioning of the gut. Cannabis helps block off bacteria and other compounds that cause inflammation in the intestines.
Helps with tremors associated with Parkinson’s disease
For those that have Parkinson’s disease cannabis can help reduce tremors and pain while also helping promote sleep. It has also shown to improve motor skills in patients.
Helps with alcoholism
Another one of the many health benefits of cannabis is that there is no doubt cannabis is much safer than alcohol. While it may not be 100% risk-free, it can be a smarter way to curb alcoholism by substituting it with cannabis.
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Thinking to buy some Bitcoin & HODL it?
But let me tell you if your private keys of Bitcoin are not safe, you are sure to be doomed.
Let me be honest and admit that:
“Your bitcoins are only as safe as their private keys”
Even the most popular Bitcoin evangelist-Andreas M. Antonopoulos has said this several times:
“Your Keys, Your Bitcoin. Not Your Keys, Not Your Bitcoin”
That’s why I am attempting to explain the concept of private keys related to Bitcoin again today and hoping that its awareness will help Bitcoiners adopt a more proactive approach in safeguarding their private keys.
So let’s begin:
Intro: Bitcoin (BTC) Private Keys
A private key of Bitcoin is just a secret alphanumeric number.
Anyone having this secret number is entitled to spend those bitcoins, and that’s why a private key of Bitcoin needs to be safeguarded very carefully.
Usually, this key resides in a Bitcoin wallet file and for those of you who aren’t familiar with a Bitcoin wallet, here is a simplistic explanation.
A Bitcoin wallet is merely a combination of a private key and a public key of bitcoins.
So if you have this combination on a piece of paper, it is called a paper wallet, or if they are present on a mobile device, it is called a mobile wallet.
To understand the concept of private keys in Bitcoin let me give you an example:
Imagine this is the 1950s:
You are Bob, who wants to send a letter to Alice. You both are friends.
Now to do this Bob needs to know Alice’s postal address or post box number. This post box number is public and is known to Alice and his friends & family, like Bob.
Moreover, Alice can always tell this post box number to anyone from whomever she wants to receive letters.
Now the real fun starts:
Let’s assume the letter has been posted in the post box but to actually receive the letter Alice needs to use her post box keys to unlock the box and take out her letters.
This key is personal to Alice, and she safeguards it cautiously because she knows that anyone in possession of this key can take her letters.
So, in this case, the post box number or address is actually the public key or public address in the Bitcoin realm and the letterbox key is like the private key of Bitcoin.
Watch this to understand more about Bitcoin key:
So, in short, a private key of Bitcoin is just a 256-bit number which can be denoted in several formats and is used to spend/send bitcoins from one address to another address.
But the most common type of private key format is this, and it usually starts from ‘5’:
Private key example: 5KVrxY3ZMQX8mWPXhLrZuvgKBMYLTiEgruhJZMbTGPEjdbQbFc7
There are many other types used for private keys and the same we are going to discuss in the next section because these formats are integral to understanding private keys of Bitcoin as a whole.
So stick with me…
Private Key Format Bitcoin
Here are some of the most popular private key formats of Bitcoin that are used in different types of wallets nowadays:
#1. Raw Private Key
A private key (in bitcoin, i.e. ECDSA SECP256K1) is a 32 byte number between 0x1 and 0xFFFF FFFF FFFF FFFF FFFF FFFF FFFF FFFE BAAE DCE6 AF48 A03B BFD2 5E8C D036 4140.
For example: 0C28FCA386C7A227600B2FE50B7CAE11EC86D3BF1FBE471BE89827E19D72AA1D
#2. Private Key WIF (WIF- Wallet Import Format)
This type of private key has 51 characters base58, starts with a ‘5’. It is also shorter and includes a checksum in case of typos. For example: 5KVrxY3ZMQX8mWPXhLrZuvgKBMYLTiEgruhJZMbTGPEjdbQbFc7
#3. Private Key WIF Compressed (WIFC- Wallet Import Format Compressed)
This type of private key has 52 characters base58, starts with a ‘K’ or ‘L.’ For example: L4ePW82Ho4p1HSiSV4dnGbvXEhfJtu1QwHatVou4vu9dAAAzzCBs
#4. Private Key Hexadecimal Format (HEX)
This private key format has 64 characters [0-9A-F] and looks like this: DD8E991C5E4F3E715C6753B4DAC6BA5C1BD50DFE8E6984A9C2CF9E6283563F39
#5. Private Key (B64)
This private key format has Base64 (44 characters) and looks like this: 3Y6ZHF5PPnFcZ1O02sa6XBvVDf6OaYSpws+eYoNWPzk=
This type of Bitcoin key format is used where space is very critical such as on QR code cards or on physical Bitcoin. Mini keys look like this: SzavMBLoXU6kDrqtUVmffv
What Is A Bitcoin Public Key (or Address)?
Bitcoin public key is another alphanumeric number associated with Bitcoin on which bitcoins are sent or received.
And the fun fact is, Bitcoin public keys (or address) are derived from private keys of Bitcoin only by applying mathematical operations over the private keys by using Elliptic Curve Cryptography (ECC)
Furthermore, these public keys can be transformed into Bitcoin public addresses, and each of the transformation from private key to the public key to public address is irreversible.
And this irreversibility by maths has been the foundation of Bitcoin-world’s first fully functional cryptocurrency.
This is how a transformed public key looks like and it usually starts from digit ‘1’ and recently due to segwit addresses you will find public addresses or keys starting from digit ‘3’ also.
Public key example: 1CuzgGMPNLuCd3AWpG53H2qnFaDANq1z5X
How Do Bitcoin Keys Work?
Bitcoin is essentially a messaging system based on public-key cryptography or better known as asymmetric cryptography that uses two systems of keys for super-efficient encryption and communication.
Bitcoin uses public keys (or address) and private keys to encrypt and decrypt data (transactions value-bitcoins).
The keys are simply large numbers that have been paired together but are not identical (asymmetric). One key in the pair can be shared with everyone; it is called the public key.
The other key in the pair is kept secret; it is called the private key. Either of the keys can be used to encrypt a message; the opposite key from the one used to encrypt the message is used for decryption. (Source-techtarget.com)
See this to understand it fully:
In Bitcoin, it is ensured that the sender is the real owner of the account from which he/she is sending and this happens through signatures that are verified by this asymmetric algorithm or function.
And this ‘signature’ is a number that proves that a signing operation took place by the right full owner of the key or bitcoins.
A signature is mathematically generated from the hash of a transaction message plus the private key and is an irreversible mathematical operation.
And further, anyone can feed the known public key and this signature in a special cryptographic function to determine that the signature was originally produced from the hash of the transaction message plus the private key, without needing to know the private key.
This ensures that the sender/signer is the real owner of bitcoins.
How Is A Bitcoin Private Key Generated?
Elliptic Curve Digital Signature Algorithm or ECDSA is the asymmetric cryptographic algorithm used by Bitcoin to generate public and private keys.
And this asymmetricity ensures that funds can be spent by the rightful owners only.
How To Keep Your Private Keys Safe?
By now it would have been clear that ‘Private Keys Of Bitcoin’ are the most important.
But if we speak strictly, there are no bitcoins at all, these are simply numeric entries on the ledger.
And holding the right private keys gives you the privilege to add or subtract these entries on a specific address of the Bitcoin ledger or transfer these numeric entries to another address within the Bitcoin’s blockchain.
That’s why safeguarding your private keys is of paramount importance.
This can be easily done by using a good Bitcoin wallet and by following necessary security practices. And that’s what we are going to discuss in this section.
So let’s start:
#1. Hardware Wallets
Hardware devices that stores your private and public keys are generally known as hardware wallets. And let me tell you some very good hardware wallets are available in the market. For example Ledger Nano X & Ledger Nano S.
#2. Mobile Wallets
A bitcoin wallet software on a mobile-based client is called mobile wallets, and these wallets are some-what secure in handling your private keys of bitcoins.
Don’t store a large sum of funds on Mobile wallets. Instead, use hardware wallets for storing large amounts of bitcoins.
#3. Desktop Wallets
Bitcoin wallet software clients installable on Windows, Mac, or Linux are called desktop wallets, and they are generally considered less secure than mobile wallets.
But if you use them with proper encryption and firewall settings, these wallets should be good to store a significant amount of bitcoins.
#4. Web Wallets
Web wallets are those wallets that exist purely on the internet and are accessible only through a browser are called web wallets.
Not recommended to store bitcoins here because you can easily be scammed by a phishing attack or a malware attack,
#5. Paper Wallets
Paper wallets are simply a piece of paper with bitcoin private and public keys printed on it.
If you know how to use paper Bitcoin wallet properly, you may go ahead storing your bitcoins here but if you don’t know, use hardware wallets for the safe side.
#6. Brain Wallets
First thing first…
A Brain wallet for storing bitcoins is a bad idea because the human brain is highly predictable and usually thinks of simple numbers/patterns to generate private keys.
And this nature can be highly predictable as well as lethal.
For example, see this public key:
This key is generated from digit ‘1’ as the brain wallet private key, and if you see it on the blockchain explorer, you will find that 1000s of transactions have happened on this address and a total of approx 7 BTC existed on this address.
So if you choose this address to store your bitcoins, it is 100% sure that your coins will be taken because digit ‘1’ as the private key is too predictable and already known.
What Is Private key Used For?
Private keys are used for unlocking your bitcoins locked on a Public address. Having a private key for a particular Public address on which unspent coins are present is like having a right of ownership and right to spend them.
This is a marvel of public-key cryptography, one of the main four ingredients which makes Bitcoin possible !!
Does Each Bitcoin Have A Private Key?
Yes & No both.
Each Bitcoin can be split upto 10^8 and the smallest unit being satoshi. So it would be correct to say for each satoshi unit or a collection of satoshis which are unspent on a Public address will have a corresponding private key.
What Is BTC Private Key Safeguarding Tips?
Some Actionable Security Practices To Safeguard Private Keys…
- Private key encryption is one smart way of safeguarding your keys if you are using a mobile or desktop wallet. But do remember that this encryption password needs to be hard to guess or brute force.
- Use the right firewall settings and use malware & antivirus protection softwares.
- Use passphrase and salt both in your private key or seed. (this is a bit complex, but if you understand you can do that…)
- If you are using a paper Bitcoin wallet, keep your BTC paper wallet in fireproof, waterproof and ink proof environments to safeguard your private keys on it.
- Be aware of phishing attacks trying to fetch your private key from your web or mobile wallet.
And if you do these things and use the recommended types of wallets, you will be OKAY.
So that’s all I wanted to share in this article. So now if you have any questions or suggestions regarding it then do express those in the comments section below.
And if you think this article was helpful to you or can help some of your friends be cautious then do share it with them 🙂
In cryptocurrencies, a private key allows a user to gain access to their wallet. The person who holds the private key fully controls the coins in that wallet. For this reason, you should keep it secret. And if you really want to generate the key yourself, it makes sense to generate it in a secure way.
Here, I will provide an introduction to private keys and show you how you can generate your own key using various cryptographic functions. I will provide a description of the algorithm and the code in Python.
Do I need to generate a private key?
Most of the time you don’t. For example, if you use a web wallet like Coinbase or Blockchain.info, they create and manage the private key for you. It’s the same for exchanges.
Mobile and desktop wallets usually also generate a private key for you, although they might have the option to create a wallet from your own private key.
So why generate it anyway? Here are the reasons that I have:
- You want to make sure that no one knows the key
- You just want to learn more about cryptography and random number generation (RNG)
What exactly is a private key?
Formally, a private key for Bitcoin (and many other cryptocurrencies) is a series of 32 bytes. Now, there are many ways to record these bytes. It can be a string of 256 ones and zeros (32 * 8 = 256) or 100 dice rolls. It can be a binary string, Base64 string, a WIF key, mnemonic phrase, or finally, a hex string. For our purposes, we will use a 64 character long hex string.The same private key, written in different formats.
Why exactly 32 bytes? Great question! You see, to create a public key from a private one, Bitcoin uses the ECDSA, or Elliptic Curve Digital Signature Algorithm. More specifically, it uses one particular curve called secp256k1.
Now, this curve has an order of 256 bits, takes 256 bits as input, and outputs 256-bit integers. And 256 bits is exactly 32 bytes. So, to put it another way, we need 32 bytes of data to feed to this curve algorithm.
There is an additional requirement for the private key. Because we use ECDSA, the key should be positive and should be less than the order of the curve. The order of secp256k1 is
FFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFEBAAEDCE6AF48A03BBFD25E8CD0364141, which is pretty big: almost any 32-byte number will be smaller than it.
So, how do we generate a 32-byte integer? The first thing that comes to mind is to just use an RNG library in your language of choice. Python even provides a cute way of generating just enough bits:
import random bits = random.getrandbits(256) bits_hex = hex(bits) private_key = bits_hex[2:]
Looks good, but actually, it’s not. You see, normal RNG libraries are not intended for cryptography, as they are not very secure. They generate numbers based on a seed, and by default, the seed is the current time. That way, if you know approximately when I generated the bits above, all you need to do is brute-force a few variants.
When you generate a private key, you want to be extremely secure. Remember, if anyone learns the private key, they can easily steal all the coins from the corresponding wallet, and you have no chance of ever getting them back.
So let’s try to do it more securely.
Cryptographically strong RNG
Along with a standard RNG method, programming languages usually provide a RNG specifically designed for cryptographic operations. This method is usually much more secure, because it draws entropy straight from the operating system. The result of such RNG is much harder to reproduce. You can’t do it by knowing the time of generation or having the seed, because there is no seed. Well, at least the user doesn’t enter a seed — rather, it’s created by the program.
In Python, cryptographically strong RNG is implemented in the
secrets module. Let’s modify the code above to make the private key generation secure!
import secrets bits = secrets.randbits(256) bits_hex = hex(bits) private_key = bits_hex[2:]
That is amazing. I bet you wouldn’t be able to reproduce this, even with access to my PC. But can we go deeper?
There are sites that generate random numbers for you. We will consider just two here. One is random.org, a well-known general purpose random number generator. Another one is bitaddress.org, which is designed specifically for Bitcoin private key generation.
Can random.org help us generate a key? Definitely, as they have service for generating random bytes. But two problems arise here. Random.org claims to be a truly random generator, but can you trust it? Can you be sure that it is indeed random? Can you be sure that the owner doesn’t record all generation results, especially ones that look like private keys? The answer is up to you. Oh, and you can’t run it locally, which is an additional problem. This method is not 100% secure.
Now, bitaddress.org is a whole different story. It’s open source, so you can see what’s under its hood. It’s client-side, so you can download it and run it locally, even without an Internet connection.
So how does it work? It uses you — yes, you — as a source of entropy. It asks you to move your mouse or press random keys. You do it long enough to make it infeasible to reproduce the results.The process of generation an entropy by randomly moving the mouse. The large chunk of symbols shows the pool.
Are you interested to see how bitaddress.org works? For educational purposes, we will look at its code and try to reproduce it in Python.
Quick note: bitaddress.org gives you the private key in a compressed WIF format, which is close to the WIF format that we discussed before. For our purposes, we will make the algorithm return a hex string so that we can use it later for a public key generation.
Bitaddress: the specifics
Bitaddress creates the entropy in two forms: by mouse movement and by key pressure. We’ll talk about both, but we’ll focus on the key presses, as it’s hard to implement mouse tracking in the Python lib. We’ll expect the end user to type buttons until we have enough entropy, and then we’ll generate a key.
Bitaddress does three things. It initializes byte array, trying to get as much entropy as possible from your computer, it fills the array with the user input, and then it generates a private key.
Bitaddress uses the 256-byte array to store entropy. This array is rewritten in cycles, so when the array is filled for the first time, the pointer goes to zero, and the process of filling starts again.
The program initiates an array with 256 bytes from window.crypto. Then, it writes a timestamp to get an additional 4 bytes of entropy. Finally, it gets such data as the size of the screen, your time zone, information about browser plugins, your locale, and more. That gives it another 6 bytes.
After the initialization, the program continually waits for user input to rewrite initial bytes. When the user moves the cursor, the program writes the position of the cursor. When the user presses buttons, the program writes the char code of the button pressed.
Finally, bitaddress uses accumulated entropy to generate a private key. It needs to generate 32 bytes. For this task, bitaddress uses an RNG algorithm called ARC4. The program initializes ARC4 with the current time and collected entropy, then gets bytes one by one 32 times.
This is all an oversimplification of how the program works, but I hope that you get the idea. You can check out the algorithm in full detail on Github.
Doing it yourself
For our purposes, we’ll build a simpler version of bitaddress. First, we won’t collect data about the user’s machine and location. Second, we will input entropy only via text, as it’s quite challenging to continually receive mouse position with a Python script (check PyAutoGUI if you want to do that).
That brings us to the formal specification of our generator library. First, it will initialize a byte array with cryptographic RNG, then it will fill the timestamp, and finally it will fill the user-created string. After the seed pool is filled, the library will let the developer create a key. Actually, they will be able to create as many private keys as they want, all secured by the collected entropy.
Initializing the pool
Here we put some bytes from cryptographic RNG and a timestamp.
__seed_byte are two helper methods that insert the entropy into our pool array. Notice that we use
def __init_pool(self): for i in range(self.POOL_SIZE): random_byte = secrets.randbits(8) self.__seed_byte(random_byte) time_int = int(time.time()) self.__seed_int(time_int) def __seed_int(self, n): self.__seed_byte(n) self.__seed_byte(n >> 8) self.__seed_byte(n >> 16) self.__seed_byte(n >> 24) def __seed_byte(self, n): self.pool[self.pool_pointer] ^= n & 255 self.pool_pointer += 1 if self.pool_pointer >= self.POOL_SIZE: self.pool_pointer = 0
Seeding with input
Here we first put a timestamp and then the input string, character by character.
def seed_input(self, str_input): time_int = int(time.time()) self.__seed_int(time_int) for char in str_input: char_code = ord(char) self.__seed_byte(char_code)
Generating the private key
This part might look hard, but it’s actually very simple.
First, we need to generate 32-byte number using our pool. Unfortunately, we can’t just create our own
random object and use it only for the key generation. Instead, there is a shared object that is used by any code that is running in one script.
What does that mean for us? It means that at each moment, anywhere in the code, one simple
random.seed(0) can destroy all our collected entropy. We don’t want that. Thankfully, Python provides
setstate methods. So, to save our entropy each time we generate a key, we remember the state we stopped at and set it next time we want to make a key.
Second, we just make sure that our key is in range (1,
CURVE_ORDER). This is a requirement for all ECDSA private keys. The
CURVE_ORDER is the order of the secp256k1 curve, which is
Finally, for convenience, we convert to hex, and strip the ‘0x’ part.
def generate_key(self): big_int = self.__generate_big_int() big_int = big_int % (self.CURVE_ORDER — 1) big_int = big_int + 1 key = hex(big_int)[2:] return key def __generate_big_int(self): if self.prng_state is None: seed = int.from_bytes(self.pool, byteorder=’big’, signed=False) random.seed(seed) self.prng_state = random.getstate() random.setstate(self.prng_state) big_int = random.getrandbits(self.KEY_BYTES * 8) self.prng_state = random.getstate() return big_int
Let’s try to use the library. Actually, it’s really simple: you can generate a private key in three lines of code!
kg = KeyGenerator() kg.seed_input(‘Truly random string. I rolled a dice and got 4.’) kg.generate_key() # 60cf347dbc59d31c1358c8e5cf5e45b822ab85b79cb32a9f3d98184779a9efc2
You can see it yourself. The key is random and totally valid. Moreover, each time you run this code, you get different results.
As you can see, there are a lot of ways to generate private key. They differ in simplicity and security.
Generating a private key is only a first step. The next step is extracting a public key and a wallet address that you can use to receive payments. The process of generating a wallet differs for Bitcoin and Ethereum, and I plan to write two more articles on that topic.
If you want to play with the code, I published it to this Github repository.
I am making a course on cryptocurrencies here on freeCodeCamp News. The first part is a detailed description of the blockchain.
I also post random thoughts about crypto on Twitter, so you might want to check it out.
First impressions are important, so why be boring when there are so many other ways to greet a person and forge a unique connection. Celebrate World Hello Day by trying out a new salutation.
1. WHAT'S THE CRAIC?
How they say “What’s up?” in Ireland. The craic (pronounced “crack”) is the news, gossip, latest goings-on, or the fun times to be planned.
2. HOW HOPS IT?
Be classically cool with this late 19th-century slang for “How’s it going?”
Add a little jaunty excitement by getting into pirate mode.
4. [HAT TIP]
Be the strong, silent type and forgo words entirely with an elegant tip of your hat.
5. THERE HE/SHE IS!
Make someone feel like the man or the woman of the hour.
Feeling friendly and cosmopolitan? Ciao will set the mood. Add a kiss on each cheek for authenticity.
Want to write a letter with a classical Latin feel? Open with this abbreviation for Salute plurimam dicit. Si vales, bene est, ego valeo. “Many greetings. If you’re well, then that’s good, and I’m well too.”
Show off your verbal dexterity with this gentleman’s greeting.
Or keep it simple and use the word that means just what it says.
Keep it casual, cowpoke, or get fancier with a full-on Howdydo?
Bring a little mellow sunshine to your interactions by greeting the Hawaiian way.
Start with a show of respect. This peaceful greeting comes from the Sanskrit for “I bow to you.”
13. HOW'S TRICKS?
You’ve got to smile when you dust off this gem from the 1920s.
14. BREAKER, BREAKER
Open the conversation like a trucker on a CB radio.
15. WELL, LOOK AT YOU!
Reminiscent of the sweet way your grandma used to express how impressed she was with you. Why not spread the love around with this opening?
This article originally ran in 2014.