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Miami Mayor Francis Suarez has been celebrating the success of a receethereum classic hard fork date 2021nt initiative to fund municipal projects through the proceeds of a city-specific crypto protocol built atop the Bitcoin (BTC) blockchain.

KEY TAKEAWAYSgrimes crypto art nftA cryptocurrency, broadly defined, is are a form of digital token or “coins” that exist on a distributed and decentralized ledger called a blockchain.

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Beyond that, the field of cryptocurrencies has expanded dramatically since Bitcoin was launched over a decade ago, and the next great digital token may be released tomorrow.Bitcoin continues to lead the pack of cryptocurrencies in terms of market capitalization, user base, and popularity.Other virtual currencies such as Ethereum are being used to create decentralized financial systems for those without access to traditional financial products.Some altcoins are being endorsed as they have newer features than Bitcoin, such as the ability to handle more transactions per second or use different consensus algorithms like proof-of-stake.What Are Cryptocurrencies?

Before we take a closer look at some of these alternatives to Bitcoin, let’s step back and briefly examine what we mean by terms like cryptocurrency and altcoin. A cryptocurrency, broadly defined, is virtual or digital money that takes the form of tokens or “coins.” While some cryptocurrencies have ventured into the physical world with credit cards or other projects, the large majority remain entirely intangible.The “crypto” in cryptocurrencies refers to complicated cryptography that allows for the creation and processing of digital currencies and their transactions across decentralized systems. Alongside this important “crypto” feature of these currencies is a common commitment to decentralization; cryptocurrencies are typically developed as code by teams who build in mechanisms for issuance (often, although not always, through a process called “mining”) and other controls.Generating a hash is not really work, though. The process is so quick and easy that bad actors could still spam the network and perhaps, given enough computing power, pass off fraudulent transactions a few blocks back in the chain. So the Bitcoin protocol requires proof of work.

It does so by throwing miners a curveball: Their hash must be below a certain target. That's why block #480504's hash starts with a long string of zeroes. It's tiny. Because every string of data will generate one and only one hash, the quest for a sufficiently small one involves adding nonces ("numbers used once") to the end of the data. So a miner will run [thedata]. If the hash is too big, she will try again. [thedata]1. Still too big. [thedata]2. Finally, [thedata]93452 yields her a hash beginning with the requisite number of zeroes.The mined block will be broadcast to the network to receive confirmations, which take another hour or so, though occasionally much longer, to process. (Again, this description is simplified. Blocks are not hashed in their entirety but broken up into more efficient structures called Merkle trees.)Depending on the kind of traffic the network is receiving, Bitcoin's protocol will require a longer or shorter string of zeroes, adjusting the difficulty to hit a rate of one new block every 10 minutes. As of October 2019, the current difficulty is around 6.379 trillion, up from 1 in 2009. As this suggests, it has become significantly more difficult to mine Bitcoin since the cryptocurrency launched a decade ago.Mining is intensive, requiring big, expensive rigs and a lot of electricity to power them. And it's competitive. There's no telling what nonce will work, so the goal is to plow through them as quickly as possible.

Early on, miners recognized that they could improve their chances of success by combining into mining pools, sharing computing power, and divvying the rewards up among themselves. Even when multiple miners split these rewards, there is still ample incentive to pursue them. Every time a new block is mined, the successful miner receives a bunch of newly created bitcoins. At first, it was 50, but then it halved to 25, and now it is 12.5 (about $119,000 in October 2019).The reward will continue to halve every 210,000 blocks, or about every four years, until it hits zero. At that point, all 21 million bitcoins will have been mined, and miners will depend solely on fees to maintain the network. When Bitcoin was launched, it was planned that the total supply of the cryptocurrency would be 21 million tokens.

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The fact that miners have organized themselves into pools worries some. If a pool exceeds 50% of the network's mining power, its members could potentially spend coins, reverse the transactions, and spend them again. They could also block others' transactions. Simply put, this pool of miners would have the power to overwhelm the distributed nature of the system, verifying fraudulent transactions by virtue of the majority power it would hold.That could spell the end of Bitcoin, but even a so-called 51% attack would probably not enable the bad actors to reverse old transactions because the proof of work requirement makes that process so labor-intensive. To go back and alter the blockchain, a pool would need to control such a large majority of the network that it would probably be pointless. When you control the whole currency, with whom can you trade?A 51% attack is a financially suicidal proposition from the miners' perspective. When GHash.io, a mining pool, reached 51% of the network's computing power in 2014, it voluntarily promised to not exceed 39.99% of the Bitcoin hash rate in order to maintain confidence in the cryptocurrency's value. Other actors, such as governments, might find the idea of such an attack interesting, though. But again, the sheer size of Bitcoin's network would make this overwhelmingly expensive, even for a world power.Another source of concern related to miners is the practical tendency to concentrate in parts of the world where electricity is cheap, such as China, or, following a Chinese crackdown in early 2018, Quebec.

Bitcoin TransactionsFor most individuals participating in the Bitcoin network, the ins and outs of the blockchain, hash rates, and mining are not particularly relevant. Outside of the mining community, Bitcoin owners usually purchase their cryptocurrency supply through a Bitcoin exchange. These are online platforms that facilitate transactions of Bitcoin and, often, other digital currencies.El Salvador made Bitcoin legal tender on June 9, 2021.1 It is the first country to do so. The cryptocurrency can be used for any transaction where the business can accept it. The U.S. dollar continues to be El Salvador’s primary currency.Bitcoin exchanges such as Coinbase bring together market participants from around the world to buy and sell cryptocurrencies. These exchanges have been both increasingly popular (as Bitcoin's popularity itself has grown in recent years) and fraught with regulatory, legal, and security challenges. With governments around the world viewing cryptocurrencies in various ways—as currency, as an asset class, or any number of other classifications—the regulations governing the buying and selling of bitcoins are complex and constantly shifting.

Perhaps even more important for Bitcoin exchange participants than the threat of changing regulatory oversight, however, is that of theft and other criminal activity. Though the Bitcoin network itself has largely been secure throughout its history, individual exchanges are not necessarily the same. Many thefts have targeted high-profile cryptocurrency exchanges, often resulting in the loss of millions of dollars worth of tokens. The most famous exchange theft is likely from Mt. Gox, which dominated the Bitcoin transaction space up through 2014. Early in that year, the platform announced the probable theft of roughly 850,000 BTC worth close to $450 million at the time. Mt. Gox filed for bankruptcy and shuttered its doors; to this day, the majority of that stolen bounty (which would now be worth a total of about $8 billion) has not been recovered.Keys and Wallets

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For these reasons, it's understandable that Bitcoin traders and owners will want to take any possible security measures to protect their holdings. To do so, they utilize keys and wallets.Bitcoin ownership essentially boils down to two numbers, a public key and a private key. A rough analogy is a username (public key) and a password (private key). A hash of the public key called an address is the one displayed on the blockchain. Using the hash provides an extra layer of security.

To receive bitcoins, it's enough for the sender to know your address. The public key is derived from the private key, which you need to send bitcoins to another address. The system makes it easy to receive money but requires verification of identity to send it.To access bitcoins, you use a wallet, which is a set of keys. These can take different forms, from third-party web applications offering insurance and debit cards, to QR codes printed on pieces of paper. The most important distinction is between "hot" wallets, which are connected to the Internet and therefore vulnerable to hacking, and "cold" wallets, which are not connected to the Internet. In the Mt. Gox case above, it is believed that most of the BTC stolen were taken from a hot wallet. Still, many users entrust their private keys to cryptocurrency exchanges, which is essentially a bet that those exchanges will have stronger defenses against the possibility of theft than one's own computer would.Bitcoin offers an efficient means of transferring money over the Internet and is controlled by a decentralized network with a transparent set of rules, thus presenting an alternative to central bank-controlled fiat money.1 There has been a great deal of talk about how to price Bitcoin, and we set out here to explore what the cryptocurrency's price might look like in the event it achieves further widespread adoption. First, however, it is useful to back up a step. Bitcoin and other digital currencies have been touted as alternatives to fiat money. But what gives any type of currency value?The currency ticker used for bitcoin is either BTC or XBT.KEY TAKEAWAYSA bitcoin exchange acts as the intermediary between a seller and a buyer or, to use cryptocurrency language, between a "maker" and a "taker."

A bitcoin exchange works like a brokerage, and you can deposit money via bank transfer, wire, and other common means of deposit. However, you will often pay a price for this service.If a trader wants to trade between cryptocurrencies, they will pay a currency conversion fee, similar to institutional banks when you trade money from different countries.

Purchases and sales are based on the same ordering system as existing brokerages, where a buyer (taker) places a limit order which is then sold when a corresponding cryptocurrency is available from the seller (maker).Understanding Bitcoin Exchanges

Bitcoin exchange platforms match buyers with sellers. Like a traditional stock exchange, traders can opt to buy and sell bitcoin by inputting either a market order or a limit order. When a market order is selected, the trader is authorizing the exchange to trade the coins for the best available price in the online marketplace. With a limit order set, the trader directs the exchange to trade coins for a price below the current ask or above the current bid, depending on whether they are buying or selling.To transact in bitcoin on an exchange, a user has to register with the exchange and go through a series of verification processes to authenticate their identity. Once the authentication is successful, an account is opened for the user who then has to transfer funds into this account before they can buy coins.

Different exchanges have different payment methods that can be used for depositing funds including bank wires, direct bank transfers, credit or debit cards, bank drafts, money orders and even gift cards. A trader who would like to withdraw money from the account could do so using the options provided by their exchange, which could include a bank transfer, PayPal transfer, check mailing, cash delivery, bank wire, or credit card transfer.Decentralized ExchangesDecentralized bitcoin exchanges are those that are operated without a central authority. These exchanges allow peer-to-peer trading of digital currencies without the need for an exchange authority to facilitate the transactions.There are a number of benefits to decentralized exchanges. First, many cryptocurrency users feel that decentralized exchanges better match the decentralized structures of most digital currencies themselves; many decentralized exchanges also require less personal information from their members than other types of exchanges. Second, if users transfer assets directly to other users, that eliminates the need for the transferring of assets to the exchange, thereby reducing the risk of theft from hacks and other fraud. Third, decentralized exchanges may be less susceptible to price manipulation and other fraudulent trading activity.

On the other hand, decentralized exchanges (like all cryptocurrency exchanges) must maintain a fundamental level of user interest in the form of trading volume and liquidity. Not all decentralized exchanges have been able to achieve these important baseline qualities. Further, users of a decentralized exchange may have less recourse if they are the victims of fraud than those who make use of exchanges with centralized authorities.Special Considerations

FeesMaking deposits and withdrawals comes at a price, depending on the payment method chosen to transfer funds. The higher the risk of a chargeback from a payment medium, the higher the fee. Making a bank draft or wiring money to the exchange has a lesser risk of a chargeback compared to funding your account with PayPal or a credit/debit card where the funds being transferred can be reversed and returned to the user upon request to the bank.

In addition to transaction fees and funds transfer fees, traders may also be subject to currency conversion fees, depending on the currencies that are accepted by the bitcoin exchange. If a user transfers Canadian dollars to an exchange that only deals in U.S. dollars, the bank or the exchange will convert the CAD to USD for a fee. Transacting with an exchange that accepts your local currency is the best way to avoid the FX fee.All bitcoin exchanges have transaction fees that are applied to each completed buy and sell order carried out within the exchange. The fee rate is dependent on the volume of bitcoin transactions that is conducted.

Foreign exchange spreads are important measures when transacting in bitcoin and vary depending on how liquid the bitcoin exchange is.Bitcoin WalletsNote that a bitcoin exchange is different from a bitcoin wallet. While the former offers a platform through which bitcoin buyers and sellers can transact with each other, the latter is simply a digital storage service for bitcoin holders to store their coins securely. To be more technical, bitcoin wallets store private keys which are used to authorize transactions and access the bitcoin address of a user. Most bitcoin exchanges provide bitcoin wallets for their users, but may charge a fee for this service.Makers and Takers

Online bitcoin marketplaces usually designate bitcoin participants as either makers or takers. When a buyer or seller places a limit order, the exchange adds it to its order book until the price is matched by another trader on the opposite end of the transaction. When the price is matched, the buyer or seller who set the limit price is referred to as a maker. A taker is a trader who places a market order that immediately gets filled.Example of a Bitcoin Exchange

For example, on a bitcoin exchange, three coin sellers are asking for BTC/USD 2265.75, BTC/USD 2269.55, and BTC/USD 2270.00. A trader who initiates a market order to buy bitcoins will have their order filled at the best ask price of 2265.75. If only five bitcoins are available for the best ask and 10 coins are available for 2269.55, and the trader wants to buy 10 at market price, the trader's order will be filled with 5 coins @ 2265.75 and the remaining 5 @ 2269.55.However, a trader who thinks they can get bitcoins for a better price could set a limit order for, say, 2260.10. If a seller matches their ask price with this order or sets a price below this figure, the order will get filled. All of this is done by the exchange, which takes a percentage of each transaction for their business.

Bengaluru | Mumbai: Andreessen Horowitz is in talks to invest in CoinSwitch Kuber, a cryptocurrency platform for retail traders, people familiar with the matter said. If the deal goes through it will be the first bet by a16z—as the Silicon Valley venture capital firm is popularly known—in an Indian startup, sources told ET.“The deal is likely to be completed soon and could be made official later this month,” one of the people cited above said.

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Perspectives of a 2x entrepreneur turned VC at @UpfrontVC#

Mark Suster

Written by

2x entrepreneur. Sold both companies (last to salesforce.com). Turned VC looking to invest in passionate entrepreneurs 〞 I*m on Twitter at @msuster

Both Sides of the Table

Perspectives of a 2x entrepreneur turned VC at @UpfrontVC, the largest and most active early-stage fund in Southern California. Snapchat: msuster

Mark Suster

Written by

2x entrepreneur. Sold both companies (last to salesforce.com). Turned VC looking to invest in passionate entrepreneurs 〞 I*m on Twitter at @msuster

Both Sides of the Table

Perspectives of a 2x entrepreneur turned VC at @UpfrontVC, the largest and most active early-stage fund in Southern California. Snapchat: msuster