How Does Cryptocurrency Work?

iStock/Marc Bruxelle
iStock/Marc Bruxelle

In September 2018, the Official Scrabble Players Dictionary added hundreds of new words—one of which was “bitcoin.” Sure, you can get a double letter score for it, but how does cryptocurrency work? And what about the other equally mysterious cryptocurrencies, which have been called everything from the future of money to a pyramid scheme? What is all this fuss about?

THE ISLAND OF YAP

One of the most popular metaphors for how cryptocurrencies work involves the Pacific island of Yap. According to NPR, the residents long ago learned of a distant island with large limestone deposits. The islanders brought back large discs of rock which they eventually turned into a form of currency—not for every day purchases, but for major outlays.

That may sound simple, but it’s not quite that easy. These rocks could weigh as much as a car, so when they changed hands they were rarely actually moved. The society just recognized that “this rock now belongs to person B.”

There’s even a story in which a giant rock brought back to Yap was lost when the boat it was on sank. The islanders dealt with this conundrum by having an oral transaction history, so everyone knew that the rock was not lost. It did have a new owner. In fact, you could argue that they had a kind of public ledger, because everyone knew how many rocks everyone had. Disagreements rarely arose because of the distributed nature of that information. This is akin to one of the most important elements of cryptocurrency: the blockchain.

At its core, the blockchain is just a ledger distributed across a network of computers, which are called nodes. Every time any transaction occurs, the network checks to make sure that it’s a valid transaction and the blockchain gets updated with a new "block," which serves as a permanent record of the transaction. This gets sent to all of the relevant computers—like the Yap islanders telling everyone about the change of ownership of a rock. The block is added to the blockchain alongside a code called a hash.

SECURITY

The hash is essentially a digital fingerprint generated by complex mathematics. This is part of the system’s security, as it takes time and energy to generate these hashes. As Reuters explains, any change to the input creates a new hash. By way of example, they explained that the extremely long novel War and Peace might have a hash like:

a948904f2f0f479b8f8197694b30184b0d2ed1c1cd2a1ec0fb85d299a192a447

While just deleting one comma from the text changes it to:

40115cc2aecc43ea86a7e54be6f7257abff7b43959cd728f06c0c7423039166r

By itself, this is not necessarily secure. But every new block also contains the previous hash as a kind of error check. If someone goes in to retroactively change a transaction (say, by deleting that comma in War and Peace), that block's hash gets updated to a new code. But the next block will have a different hash code on record from the previous block (it will be looking for the old hash, the one beginning with a948—but seeing the new hash, the one starting with 4011), so in theory the nefarious action will be discovered. There are potential ways to cheat this system. A computer faster than the other nodes combined may be able to rewrite blocks fast enough to work, but MIT Technology Review cautioned that even then “success isn’t guaranteed.”

CRYPTOCURRENCY

But cryptocurrencies and blockchains are not synonymous. Similarly to how the internet and world wide web are not synonymous, blockchain is a technology chiefly used for cryptocurrencies, though this may not always be the case. It’s increasingly being examined for use in other fields—and some even argue cryptocurrency is one of the least promising fields.

The crypto in cryptocurrency is a reference to the cryptography used to ensure that the transactions are secure. Up until this stage, it’s not particularly different from any other digital currency—when you send U.S. dollars over the internet, physical dollars are not changing hands. That’s true for any digital currency, of which cryptocurrencies are one.

But there are key differences—including that, traditionally, money is issued by the government or some powerful institution. Cryptocurrencies are created by algorithms. Another important distinction is how ownership is traced. Because there’s nothing physical to a cryptocurrency, the blockchain ledger is used to determine ownership.

There are also more nuanced differences. Because the blockchain ledger has to be transparent, all transactions are public, leading to many suggestions for how to best manage privacy expectations. As another distinction, many cryptocurrencies are limited to a set number—only 21 million bitcoins will ever exist, and it remains unclear what will happen when the final bitcoin is "mined." Contrast that with traditional currency, which can be produced in limitless quantities.

Not everyone is convinced that cryptocurrencies are the future. Speaking to Vox, Nicholas Weaver of the International Computer Science Institute at UC Berkeley explained that miners—the people who create the blocks and get paid for their efforts—are disproportionately powerful and serve as the central agency that cryptocurrencies are trying to avoid. Also, he argues that outside of nefarious purchases (like assassins or illegal drugs), there isn’t a point to cryptocurrencies. Due to price volatility, they don’t fundamentally work as a currency. There’s a famous story about a programmer buying two pizzas for 10,000 bitcoin—a sum that would be worth more than $80 million just a few years later. This volatility, according to Weaver, means that most companies claiming they accept bitcoin aren’t actually accepting bitcoin per se, they just instantly sell it for conventional currency.

Cryptocurrency fans immediately pounced on these comments, arguing that it’s an oversimplification and could be used to argue against other forms of currency as well. No matter what, the debates will continue.

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Amazon's Best Black Friday Deals: Tech, Video Games, Kitchen Appliances, Clothing, and More

Amazon
Amazon

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Black Friday is finally here, and Amazon is offering great deals on kitchen appliances, tech, video games, and plenty more. We will keep updating this page as sales come in, but for now, here are the best Amazon Black Friday sales to check out.

Kitchen

Instant Pot/Amazon

- Instant Pot Duo Plus 9-in-115 Quart Electric Pressure Cooker; $90 (save $40)

- Keurig K-Cafe Special Edition; $190 (save $30)

- Ninja OS301 Foodi 10-in-1 Pressure Cooker and Air Fryer; $125 (save $75)

- Nespresso Vertuo Next Coffee and Espresso Machine by Breville; $120 (save $60)

- KitchenAid KSMSFTA Sifter with Scale Attachment; $95 (save $75)

- Keurig K-Mini Coffee Maker; $60 (save $20)

- Cuisinart Bread Maker; $80 (save $97)

- Anova Culinary Sous Vide Precision Cooker; $139 (save $60)

- Aicook Juicer Machine; $35 (save $15)

- JoyJolt Double Wall Insulated Espresso Mugs - Set of Two; $14 (save $10)

- Longzon Silicone Stretch Lids - Set of 14; $16 (save $11)

- HadinEEon Milk Frother; $37 (save $33)

Home Appliances

Roomba/Amazon

- iRobot Roomba 675 Robot Vacuum with Wi-Fi Connectivity; $179 (save $101)

- ASAKUKI 500ml Premium Essential Oil Diffuser; $22 (save $4)

- Facebook Portal Smart Video Calling 10 inch Touch Screen Display with Alexa; $129 (save $50)

- Bissell air320 Smart Air Purifier with HEPA and Carbon Filters; $280 (save $50)

- Oscillating Quiet Cooling Fan Tower; $59 (save $31)

- TaoTronics PTC 1500W Fast Quiet Heating Ceramic Tower; $55 (save $10)

- Vitamix 068051 FoodCycler 2 Liter Capacity; $300 (save $100)

- Ring Video Doorbell; $70 (save $30)

Video games

Sony

- Marvel's Spider-Man: Game of The Year Edition for PlayStation 4; $20 (save $20)

- The Legend of Zelda: Link's Awakening; $40 (save $20)

- Hyrule Warriors: Age of Calamity; $50 (save $10)

- Marvel's Avengers; $25 (save $33)

- The Last of Us Part II for PlayStation 4; $30 (save $30)

- LEGO Harry Potter: Collection; $15 (save $15)

- Ghost of Tsushima; $40 (save $20)

- BioShock: The Collection; $20 (save $30)

- The Sims 4; $24 (save $20)

- God of Warfor PlayStation 4; $10 (save $10)

- Days Gonefor PlayStation 4; $20 (save $6)

- Luigi's Mansion 3 for Nintendo Switch; $40 (save $20)

Computers and tablets

Microsoft/Amazon

- New Apple MacBook Pro 16 inches with 512 GB; $2149 (save $250)

- Microsoft Surface Laptop 3 with 13.5 inch Touch-Screen; $1200 (save $400)

- Lenovo ThinkPad T490 Laptop; $889 (save $111)

- Amazon Fire HD 10 Tablet (64GB); $120 (save $70)

- Amazon Fire HD 10 Kids Edition Tablet (32 GB); $130 (save $70)

- Apple iPad Mini (64 GB); $335 (save $64)

- Vankyo MatrixPad S2 Tablet; $120 (save $10)

Tech, gadgets, and TVs

Apple/Amazon

- Apple Watch Series 3 with GPS; $120 (save $79)

- Seneo Wireless Charger, 3 in 1 Wireless Charging Station; $16 (save $10)

- SAMSUNG 75-inch Class Crystal 4K Smart TV; $998 (save $200)

- Nixplay 2K Smart Digital Picture Frame 9.7 Inch Silver; $238 (save $92)

- All-New Amazon Echo Dot with Clock and Alexa (4th Gen); $39 (save $21)

- MACTREM LED Ring Light 6" with Tripod Stand; $16 (save $3)

- Amazon Fire TV Stick with Alexa Voice Remote; $28 (save $12)

- DR. J Professional HI-04 Mini Projector; $93 (save $37)

Headphones and speakers

Beats/Amazon

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- Apple AirPods Pro; $169 (save $50)

- Anker Soundcore Upgraded Bluetooth Speaker; $22 (save $8)

- Powerbeats Pro Wireless Earphones; $175 (save $75)

- JBL Boombox; $280 (save $120)

Movies and TV

HBO/Amazon

- Game of Thrones: The Complete Series; $115 (save $89)

- Jurassic World 5-Movie Set; $23 (save $37)

- Deadwood: The Complete Series; $42 (save $28)

- Back to the Future Trilogy; $15 (save $21)

Toys and Games

Amazon

- Awkward Family Photos Greatest Hits; $15 (save $10)

- Exploding Kittens Card Game; $10 (save $10)

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- LEGO Ideas Ship in a Bottle 92177 Expert Building Kit; $56 (save $14)

Furniture

Casper/Amazon

- Casper Sleep Element Queen Mattress; $476 (save $119)

- ZINUS Alexis Deluxe Wood Platform Bed Frame; $135 (save $24)

- ROMOON Dresser Organizer with 5 Drawers; $59 (save $11) 

- AmazonBasics Room Darkening Blackout Window Curtains; $26 (save $5)

- Writing Desk by Caffoz; $119 (save $21)

- SPACE Seating Office Support Managers Chair; $112 (save $116)

- Rivet Globe Stick Table Lamp; $53 (save $17)

- Christopher Knight Home Merel Mid-Century Modern Club Chair; $188 (save $10)

- Walker Edison Furniture Industrial Rectangular Coffee Table; $121 (save $48)

Beauty

Haus/Amazon

- MySmile Teeth Whitening Kit with LED Light; $21 (save $12) 

- Cliganic USDA Organic Lip Balms Set of Six; $6 (save $4)

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- Native Deodorant for Men and Women Set of Three; $25 (save $11) 

- BAIMEI Rose Quartz Jade Roller & Gua Sha; $14 (save $3)

- Honest Beauty Clearing Night Serum with Pure Retinol and Salicylic Acid; $20 (save $8)

- WOW Apple Cider Vinegar Shampoo and Hair Conditioner Set; $30 (save $5) 

- La Roche-Posay Effaclar Purifying Foaming Gel Cleanser; $15 (save $5)

- wet n wild Bretman Rock Shadow Palette; $9 (save $6)

- EltaMD UV Daily Tinted Face Sunscreen Moisturizer with Hyaluronic Acid; $25 (save $6)

Clothes

Ganni/Amazon

- Ganni Women's Crispy Jacquard Dress; $200 (save $86) 

- The Drop Women's Maya Silky Slip Skirt; $36 (save $9)

- Steve Madden Women's Editor Boot; $80 (save $30)

- adidas Women's Roguera Cross Trainer; $40 (save $25)

- Line & Dot Women's Elizabeth Sweater; $74 (save $18)

- Levi's Men's Sherpa Trucker Jacket; $57 (save $41)

- Adidas Men's Essentials 3-Stripes Tapered Training Joggers Sweatpants; $28 (save $12)

- Timex Men's Weekender XL 43mm Watch; $32 (save $20)

- Ray-Ban Unisex-Adult Hexagonal Flat Lenses Sunglasses; $108 (save $46) 

- Reebok Men's Flashfilm Train Cross Trainer; $64 (save $16)

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What Is a Scuttlebutt, and Why Do We Like to Hear It?

Photo by Courtney Nuss on Unsplash

Casual conversation is home to a variety of prompts. You might ask someone how they’re doing, what’s new, or if they’ve done anything interesting recently. Sometimes, you can ask them what the scuttlebutt is. “What’s the scuttlebutt?” you’d say, for example, and then they’d reply with the solicited scuttlebutt.

We can easily infer that scuttlebutt is a slang term for information or maybe even gossip. But what exactly is scuttlebutt, and why did it become associated with idle water cooler talk?

According to Merriam-Webster, a scuttlebutt referred to a cask on sailing ships in the 1800s that contained drinking water for those on board. It was later used as the name of the drinking fountain found on a ship or in a Naval installation. The cask was known as a butt, while scuttle was taken from the French word escoutilles and means hatch or hole. A scuttlebutt was therefore a hatch in the cask.

Because sailors usually received orders from shouting supervisors, talking amongst themselves was discouraged. Since sailors could congregate around the fountain, it became a place to finally catch up and exchange gossip, making scuttlebutt synonymous with casual conversation. The scuttlebutt was really the only place to do it.

Nautical technology made the scuttlebutt obsolete, but the term endured, becoming a catch-all word for unfounded rumors.

The next time someone asks you what the scuttlebutt is, now you can tell them.

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