What is Bitcoin?

The blockchain is a shared, immutable ledger that helps businesses record transactions and track assets. The blockchain can track tangible assets like cars, houses, and land. Tangible assets like intellectual property can also be tracked on the blockchain.

Imagine a blockchain as a distributed database split among computer nodes. A blockchain stores data in blocks. When a block is full, it is closed and linked to the next. As a result, all subsequent information is compiled into a new block that will be added to the chain once it is filled.

The blockchain is designed so that adding a transaction requires consensus. That means a majority of network nodes must approve a transaction. No single authority can control transactions on the blockchain. The network nodes use cryptographic keys and passwords to validate each other's transactions.

Blockchain History

The blockchain was not as popular in 1991 when Stuart Haber and W. Scott Stornetta worked on it. The blocks were designed to prevent tampering with document timestamps. Stuart Haber and W. Scott Stornetta improved their work in 1992 by using Merkle trees to increase efficiency and collect more documents on a single block.

In 2004, he developed Reusable Proof of Work. This system allows users to verify token transfers in real time. Satoshi Nakamoto invented distributed blockchains in 2008. He improved the blockchain design so that new blocks could be added to the chain without being signed by trusted parties.

Satoshi Nakomoto mined the first Bitcoin block in 2009, earning 50 Bitcoins. Then, in 2013, Vitalik Buterin stated that Bitcoin needed a scripting language for building decentralized applications. He then created Ethereum, a new blockchain-based platform for decentralized apps. Since the Ethereum launch in 2015, different blockchain platforms have been launched: from Hyperledger by Linux Foundation, EOS.IO by block.one, IOTA, NEO and Monero dash blockchain. The block chain industry is still growing, and so are the businesses built on them.

Blockchain Components

The Blockchain is made up of many parts:

1. Node: The node is split into two parts: full and partial. The full node has the authority to validate, accept, or reject any transaction. Partial nodes or lightweight nodes only keep the transaction's hash value. It doesn't keep a full copy of the blockchain, so it has limited storage and processing power.

2. Ledger: A public database of information. A ledger can be public, decentralized, or distributed. Anyone on the blockchain can access the public ledger and add data to it. It allows each node to participate in every transaction. The distributed ledger copies the database to all nodes. A group of nodes can verify transactions or add data blocks to the blockchain.

3. Wallet: A blockchain wallet allows users to send, receive, store, and exchange digital assets, as well as monitor and manage their value. Wallets come in two flavors: hardware and software. Online or offline wallets exist. Online or hot wallets are used when online. Without an internet connection, offline wallets like paper and hardware wallets can store private keys and sign transactions. Wallets generally secure transactions with a private key and wallet address.

4. Nonce: A nonce is a short term for a "number used once''. It describes a unique random number. Nonces are frequently generated to modify cryptographic results. A nonce is a number that changes over time and is used to prevent value reuse. To prevent document reproduction, it can be a timestamp. A cryptographic hash function can also use it to vary input. Nonces can be used for authentication, hashing, or even electronic signatures.

5. Hash: A hash is a mathematical function that converts inputs of arbitrary length to outputs of fixed length. That is, regardless of file size, the hash will remain unique. A hash cannot generate input from hashed output, but it can identify a file. Hashes can be used to verify message integrity and authenticate data. Cryptographic hash functions add security to standard hash functions, making it difficult to decipher message contents or track senders.

Blockchain: Pros and Cons

The blockchain provides a trustworthy, secure, and trackable platform for business transactions quickly and affordably. The blockchain reduces paperwork, documentation errors, and the need for third parties to verify transactions.

Blockchain security relies on a system of unaltered transaction records with end-to-end encryption, reducing fraud and unauthorized activity. The blockchain also helps verify the authenticity of items like farm food, medicines, and even employee certification. The ability to control data gives users a level of privacy that no other platform can match.

In the case of Bitcoin, the blockchain can only handle seven transactions per second. Unlike Hyperledger and Visa, which can handle ten thousand transactions per second. Also, each participant node must verify and approve transactions, slowing down exchanges and limiting scalability.

The blockchain requires a lot of energy to run. In addition, the blockchain is not a hugely distributable system and it is destructible. The security of the block chain can be compromised by hackers; it is not completely foolproof. Also, since blockchain entries are immutable, data cannot be removed. The blockchain's high energy consumption and limited scalability reduce its efficiency.

Why Is Blockchain So Popular?
The blockchain is a technology giant. In 2018, 90% of US and European banks began exploring blockchain's potential. In 2021, 24% of companies are expected to invest $5 million to $10 million in blockchain. By the end of 2024, it is expected that corporations will spend $20 billion annually on blockchain technical services.

Blockchain is used in cryptocurrency, medical records storage, identity verification, election voting, security, agriculture, business, and many other fields. The blockchain offers a more secure, decentralized, and less corrupt system of making global payments, which cryptocurrency enthusiasts love. Users who want to save time and energy prefer it because it is faster and less bureaucratic than banking and healthcare systems.

Most organizations have jumped on the blockchain bandwagon, and for good reason: the blockchain industry has never had more potential. The launch of IBM's Blockchain Wire, Paystack, Aza Finance and Bloom are visible proof of the wonders that the blockchain has done. The blockchain's cryptocurrency segment may not be as popular in the future as the blockchain's other segments, as evidenced by the various industries where it is used. The blockchain is here to stay, and it will be discussed for a long time, not just in tech, but in many industries.

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War's Human Cost
I didn't start crying until I was outside a McDonald's in an Olempin, Poland rest area on highway S17.

Children pick toys at a refugee center, Olempin, Poland, March 4, 2022.

Refugee children, mostly alone with their mothers, but occasionally with a gray-haired grandfather or non-Ukrainian father, were coaxed into picking a toy from boxes provided by a kind-hearted company and volunteers.
I went to Warsaw to continue my research on my family's history during the Holocaust. In light of the ongoing Ukrainian conflict, I asked former colleagues in the US Department of Defense and Intelligence Community if it was safe to travel there. They said yes, as Poland was a NATO member.
I stayed in a hotel in the Warsaw Ghetto, where 90% of my mother's family was murdered in the Holocaust. Across the street was the first Warsaw Judenrat. It was two blocks away from the apartment building my mother's family had owned and lived in, now dilapidated and empty.

Building of my great-grandfather, December 2021.

A mass grave of thousands of rocks for those killed in the Warsaw Ghetto, I didn't cry when I touched its cold walls.

Warsaw Jewish Cemetery, 200,000–300,000 graves.

Mass grave, Warsaw Jewish Cemetery.

My mother's family had two homes, one in Warszawa and the rural one was a forest and sawmill complex in Western Ukraine. For the past half-year, a local Ukrainian historian had been helping me discover faint traces of her family’s life there — in fact, he had found some people still alive who remembered the sawmill and that it belonged to my mother’s grandfather. The historian was good at his job, and we had become close.

My historian friend, December 2021, talking to a Ukrainian.

With war raging, my second trip to Warsaw took on a different mission. To see his daughter and one-year-old grandson, I drove east instead of to Ukraine. They had crossed the border shortly after the war began, leaving men behind, and were now staying with a friend on Poland's eastern border.
I entered after walking up to the house and settling with the dog. The grandson greeted me with a huge smile and the Ukrainian word for “daddy,” “Tato!” But it was clear he was awaiting his real father's arrival, and any man he met would be so tentatively named.
After a few moments, the boy realized I was only a stranger. He had musical talent, like his mother and grandfather, both piano teachers, as he danced to YouTube videos of American children's songs dubbed in Ukrainian, picking the ones he liked and crying when he didn't.

Songs chosen by my historian friend's grandson, March 4, 2022

He had enough music and began crying regardless of the song. His mother picked him up and started nursing him, saying she was worried about him. She had no idea where she would live or how she would survive outside Ukraine. She showed me her father's family history of losses in the Holocaust, which matched my own research.
After an hour of drinking tea and trying to speak of hope, I left for the 3.5-hour drive west to Warsaw.
It was unlike my drive east. It was reminiscent of the household goods-filled carts pulled by horses and people fleeing war 80 years ago.

Jewish refugees relocating, USHMM Holocaust Encyclopaedia, 1939.

The carefully chosen trinkets by children to distract them from awareness of what is really happening and the anxiety of what lies ahead, made me cry despite all my research on the Holocaust. There is no way for them to communicate with their mothers, who are worried, absent, and without their fathers.
It's easy to see war as a contest of nations' armies, weapons, and land. The most costly aspect of war is its psychological toll. My father screamed in his sleep from nightmares of his own adolescent trauma in Warsaw 80 years ago.

Survivor father studying engineering, 1961.

In the airport, I waited to return home while Ukrainian public address systems announced refugee assistance. Like at McDonald's, many mothers were alone with their children, waiting for a flight to distant relatives.
That's when I had my worst trip experience.
A woman near me, clearly a refugee, answered her phone, cried out, and began wailing.
The human cost of war descended like a hammer, and I realized that while I was going home, she never would

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What can't Google do?
Seriously, nothing! Google rocks.
Google is a major player in online tools and services. We use it for everything, from research to entertainment.
Did I say entertain yourself?
Yes, with so many features and options, it can be difficult to fully utilize Google.

#1. Drive Google Mad

You can make Google's homepage dance if you want to be silly.
Just type “Google Gravity” into Google.com. Then select I'm lucky.
See the page unstick before your eyes!

#2 Play With Google Image

Google isn't just for work.
Then have fun with it!
You can play games right in your search results. When you need a break, google “Solitaire” or “Tic Tac Toe”. 

#3. Do a Barrel Roll

Need a little more excitement in your life? Want to see Google dance?
Type “Do a barrel roll” into the Google search bar.
Then relax and watch your screen do a 360. 

#4  No Internet?  No issue!

This is a fun trick to use when you have no internet.
If your browser shows a “No Internet” page, simply press Space.
Boom!
We have dinosaurs! Now use arrow keys to save your pixelated T-Rex from extinction.

#5 Google Can Help

Play this Google coin flip game to see if you're lucky.
Enter “Flip a coin” into the search engine.
You'll see a coin flipping animation. If you get heads or tails, click it. 

#6. Think with Google

My favorite Google find so far is the “Think with Google” website.
Think with Google is a website that offers marketing insights, research, and case studies.
I highly recommend it to entrepreneurs, small business owners, and anyone interested in online marketing. 

#7. Google Can Read Images!

This is a cool Google trick that few know about.
You can search for images by keyword or upload your own by clicking the camera icon on Google Images.
Google will then show you all of its similar images.

#8. Modify the Google Logo!

Clicking on the “I'm Feeling Lucky” button on Google.com takes you to a random Google Doodle.
Each year, Google creates a Doodle to commemorate holidays, anniversaries, and other occasions.

#9. What is my IP?

Simply type “What is my IP” into Google to find out.
Your IP address will appear on the results page.

#10. Send a Self-Destructing Email With Gmail, 

Create a new message in Gmail. Find an icon that resembles a lock and a clock near the SEND button. That's where the Confidential Mode is.
By clicking it, you can set an expiration date for your email. Expiring emails are automatically deleted from both your and the recipient's inbox.

#11. Blink, Google Blink!

This is a unique Google trick.
Type “blink HTML” into Google. The words “blink HTML” will appear and then disappear.
The text is displayed for a split second before being deleted.
To make this work, Google reads the HTML code and executes the “blink” command. 

#12. The Answer To Everything

This is for all Douglas Adams fans.
The answer to life, the universe, and everything is 42, according to Google.
An allusion to Douglas Adams' Hitchhiker's Guide to the Galaxy, in which Ford Prefect seeks to understand life, the universe, and everything.

#13. Google in 1998

It's a blast!
Type “Google in 1998” into Google. "I'm feeling lucky"
You'll be taken to an old-school Google homepage.
It's a nostalgic trip for long-time Google users. 

#14. Scholarships and Internships

Google can help you find college funding!
Type “scholarships” or “internships” into Google.
The number of results will surprise you. 

#15. OK, Google. Dice!

To roll a die, simply type “Roll a die” into Google.
On the results page is a virtual dice that you can click to roll. 

#16. Google has secret codes!

Hit the nine squares on the right side of your Google homepage to go to My Account. Then Personal Info.
You can add your favorite language to the “General preferences for the web” tab. 

#17. Google Terminal 

You can feel like a true hacker.
Just type “Google Terminal” into Google.com. "I'm feeling lucky"
Voila~!
You'll be taken to an old-school computer terminal-style page.
You can then type commands to see what happens.

Have you tried any of these activities? Tell me in the comments.

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