Wallets and similar software technically handle all bitcoins as equivalent, establishing the basic level of fungibility. Researchers have pointed out that the history of each bitcoin is registered and publicly available in the blockchain ledger, and that some users may refuse to accept bitcoins coming from controversial transactions, which would harm bitcoin's fungibility.[123] For example, in 2012, Mt. Gox froze accounts of users who deposited bitcoins that were known to have just been stolen.[124]
Ethereum was initially described in a white paper by Vitalik Buterin,[10] a programmer involved with Bitcoin Magazine, in late 2013 with a goal of building decentralized applications.[11][12] Buterin had argued that Bitcoin needed a scripting language for application development. Failing to gain agreement, he proposed development of a new platform with a more general scripting language.[4]:88
Ethereum can also be used to build Decentralized Autonomous Organizations (DAO). A DAO is fully autonomous, decentralized organization with no single leader. DAO’s are run by programming code, on a collection of smart contracts written on the Ethereum blockchain. The code is designed to replace the rules and structure of a traditional organization, eliminating the need for people and centralized control. A DAO is owned by everyone who purchases tokens, but instead of each token equating to equity shares & ownership, tokens act as contributions that give people voting rights.

^ Jump up to: a b c d e Joshua A. Kroll; Ian C. Davey; Edward W. Felten (11–12 June 2013). "The Economics of Bitcoin Mining, or Bitcoin in the Presence of Adversaries" (PDF). The Twelfth Workshop on the Economics of Information Security (WEIS 2013). Archived (PDF) from the original on 9 May 2016. Retrieved 26 April 2016. A transaction fee is like a tip or gratuity left for the miner.
من منظور المنقبين فإن سعر البيتكوين الحالي أقل بكثير مما يجب عليه أن يكون، ولهذا ستجد أنه لا رغبة لديهم في بيع العُملات التي بحوزتهم بأسعار مُنخفضة لأنهم قد استخدموا كميات هائلة من الكهرباء لإنتاجها، إضافة إلى الاستثمار في عتاد خاص للقيام بذلك. الوضع سيزداد سوءا بالنسبة إليهم ما لم ينخفض عدد المُنقبين بشكل مُعتبر، حيث أن عدد العُملات التي سيتم إنتاجها ستنخفض إلى النصف كل 4 سنوات. في المقابل، تم إنتاج كميات كبيرة من البيتكوينات بشكل رخيص جدا في بدايات العُملة لما كان عدد المُنقبين قليلا ولما كان عامل “الصعوبة” hardness منخفضا جدا، وبالتالي حاجة إلى كهرباء أقل، هذا الأمر خلق حالة من اللاتوازن داخل شبكة العُملة، حيث بإمكان أصحاب البيتكوينات القديمة بيع عُملاتهم دون تسجيل خسائر مُقارنة بمن انضموا إلى جبهة المُنقبين مؤخرا.

Various journalists,[205][210] economists,[211][212] and the central bank of Estonia[213] have voiced concerns that bitcoin is a Ponzi scheme. In April 2013, Eric Posner, a law professor at the University of Chicago, stated that "a real Ponzi scheme takes fraud; bitcoin, by contrast, seems more like a collective delusion."[214] A July 2014 report by the World Bank concluded that bitcoin was not a deliberate Ponzi scheme.[215]:7 In June 2014, the Swiss Federal Council[216]:21 examined the concerns that bitcoin might be a pyramid scheme; it concluded that, "Since in the case of bitcoin the typical promises of profits are lacking, it cannot be assumed that bitcoin is a pyramid scheme." In July 2017, billionaire Howard Marks referred to bitcoin as a pyramid scheme.[217]
In the blockchain, bitcoins are registered to bitcoin addresses. Creating a bitcoin address requires nothing more than picking a random valid private key and computing the corresponding bitcoin address. This computation can be done in a split second. But the reverse, computing the private key of a given bitcoin address, is mathematically unfeasible. Users can tell others or make public a bitcoin address without compromising its corresponding private key. Moreover, the number of valid private keys is so vast that it is extremely unlikely someone will compute a key-pair that is already in use and has funds. The vast number of valid private keys makes it unfeasible that brute force could be used to compromise a private key. To be able to spend their bitcoins, the owner must know the corresponding private key and digitally sign the transaction. The network verifies the signature using the public key; the private key is never revealed.[7]:ch. 5
This dramatic volatility attracted global attention with the mainstream media running near-daily reports on the price of Ether. The publicity generated has been a major boon for the ecosystem, attracting thousands of new developers and business ventures alike. In 2018 the amount raised through Ethereum-enabled ICOs reached almost $8bn, increasing from just $90m in 2016. While the price of Ethereum has faced extreme volatility over the years, it is this volatility which has driven interest. After every boom and bust cycle, Ethereum comes out the other side with a fundamentally stronger platform and a broader developer community backing it. These fundamental improvements would suggest a positive long-term outlook on the price of Ethereum.
Ethereum’s core innovation, the Ethereum Virtual Machine (EVM) is a Turing complete software that runs on the Ethereum network. It enables anyone to run any program, regardless of the programming language given enough time and memory. The Ethereum Virtual Machine makes the process of creating blockchain applications much easier and efficient than ever before. Instead of having to build an entirely original blockchain for each new application, Ethereum enables the development of potentially thousands of different applications all on one platform.
نيمكوين : مليون هو مجموع عملة ال نيمكوين وهذا يعني أن ال نيمكوين ستكون نادرة نسبيا، بالضبط نفس مستوى ندرة ال بيتكوين . هذا وتساعد ال نيمكوين على إنشاء الإنترنت الغير خاضعة للرقابة، وتنكر السيطرة الحكومية. وهي منصة متعددة الاستخدامات يمكن استخدامها لنظام أسماء النطاقات الغير مركزي والغير منظم، نوع من الإنترنت الخاصة بها. ويمكن أيضا أن تستخدم لإرسال الرسائل، والتصويت، ونظام تسجيل الدخول.
Ethereum-based customized software and networks, independent from the public Ethereum chain, are being tested by enterprise software companies.[48] Interested parties include Microsoft, IBM, JPMorgan Chase,[33][49] Deloitte,[50] R3,[51] Innovate UK (cross-border payments prototype).[52] Barclays, UBS and Credit Suisse are experimenting with Ethereum blockchain to automate Markets in Financial Instruments Directive (MiFID) II requirements.

Ethereum addresses are composed of the prefix "0x", a common identifier for hexadecimal, concatenated with the rightmost 20 bytes of the Keccak-256 hash (big endian) of the ECDSA public key (the curve used is the so called secp256k1, the same as Bitcoin). In hexadecimal, 2 digits represents a byte, meaning addresses contain 40 hexadecimal digits. An example of an Ethereum address is 0xb794F5eA0ba39494cE839613fffBA74279579268. Contract addresses are in the same format, however they are determined by sender and creation transaction nonce.[34] User accounts are indistinguishable from contract accounts given only an address for each and no blockchain data. Any valid Keccak-256 hash put into the described format is valid, even if it does not correspond to an account with a private key or a contract. This is unlike Bitcoin, which uses base58check to ensure that addresses are properly typed.
There are many ways you can plug into the Ethereum network, one of the easiest ways is to use its native Mist browser. Mist provides a user-friendly interface & digital wallet for users to trade & store Ether as well as write, manage, deploy and use smart contracts. Like web browsers give access and help people navigate the internet, Mist provides a portal into the world of decentralized blockchain applications.
The receiver of the first bitcoin transaction was cypherpunk Hal Finney, who created the first reusable proof-of-work system (RPoW) in 2004.[24] Finney downloaded the bitcoin software on its release date, and on 12 January 2009 received ten bitcoins from Nakamoto.[25][26] Other early cypherpunk supporters were creators of bitcoin predecessors: Wei Dai, creator of b-money, and Nick Szabo, creator of bit gold.[21] In 2010, the first known commercial transaction using bitcoin occurred when programmer Laszlo Hanyecz bought two Papa John's pizzas for ₿10,000.[27] 

لضمان صحّة عمليات التحويل، يقوم نظام البيتكوين بالاحتفاظ بسجل حسابات تُسجل فيه جميع الإجراءات التي تتم على الشبكة يُطلق عليه اسم سلسلة الكُتل (بالإنجليزية: block chain). تتشارك جميع العُقد المتواجدة على شبكة البيتكوين هذا السجل عبر نظام يعتمد على بروتوكول بِتكُيِن. تحتوي سلسلة الكُتل على جميع الإجراءات التي تمت باستخدام بِتكُيِن، وهو ما يُمكن من معرفة الرصيد الذي يملكه كل عنوان على هذه الشبكة. يُطلق على هذا المفهوم وصف السلسلة للترابط المتواجد ما بين الكُتل، حيث تحتوي كل كُتلة على هاش الكُتلة التي تسبقها ويتواصل الأمر إلى غاية الوصول إلى الكُتلة الأولى التي يُطلق عليها اسم "كتلة التكوين" (بالإنجليزية: genesis block) . تكوين السلسلة بهذه الطريقة يجعل من مهمة تغيير أي كُتلة بعد مرور مُدة مُعينة على إنشائها في غاية الصعوبة، حيث أن تغيير أي كُتلة يتطلب تغيير كل الكُتل التي تليها بسبب الحاجة إلى إعادة حساب هاش كل كُتلة لتحديث قيمة هاش الكُتلة السابقة فيها. هذه الخاصية هي ما يجعل من مُشكل الإنفاق المُتكرر لنفس العُملات في غاية الصعوبة على بِتكُيِن، بل ويُمكن اعتبار سلسلة الكُتل العمود الفقري الذي لا يُمكن لعُملة بِتكُيِن الوقوف من دونه[10].
EthereumPrice.org was developed by Ether0x in March 2016 to allow users to easily track the price of Ethereum both historically and in real-time. The platform has since evolved to include several fiat currencies (EUR, GBP, JPY and others) as well as price data for a number of Ethereum ERC20 tokens and other blockchain currencies. More recently, prediction data from Augur was also added to provide insight into the future price expectations of the Ether market. Price data is currently sourced from multiple exchanges with the weighted average price of these assets being calculated by CryptoCompare.com. For more details on the weighted average calculation, see our FAQ.

In 2016 a decentralized autonomous organization called The DAO, a set of smart contracts developed on the platform, raised a record US$150 million in a crowdsale to fund the project.[25] The DAO was exploited in June when US$50 million in ether were taken by an unknown hacker.[26][27] The event sparked a debate in the crypto-community about whether Ethereum should perform a contentious "hard fork" to reappropriate the affected funds.[28] As a result of the dispute, the network split in two. Ethereum (the subject of this article) continued on the forked blockchain, while Ethereum Classic continued on the original blockchain.[29] The hard fork created a rivalry between the two networks.

Bitcoin is a digital currency, sometimes referred to as a cryptocurrency, best known as the world's first truly decentralized digital currency. Bitcoin is traded on a peer-to-peer basis with a distributed ledger called the Blockchain, and the Bitcoin exchange rate to the US Dollar and other major currencies is determined by supply and demand as with other global exchange rates. The traded value of Bitcoin has proven volatile through various booms and busts in demand. Ultimately, however, many see Bitcoin as a store of value against government-backed fiat currencies.


Using Ethereum’s “Turing complete” smart contract language, Solidity, developers are able to deploy a set of instructions to the blockchain that operate indefinitely with a high degree of finality and fraud-resistance. With the first block being mined in July 2015, Ethereum has since become the largest smart contract platform of its kind, and the second largest blockchain of all time as measured by market capitalization.
Ethereum's blockchain uses Merkle trees, for security reasons, to improve scalability, and to optimize transaction hashing.[61] As with any Merkle tree implementation, it allows for storage savings, set membership proofs (called "Merkle proofs"), and light client synchronization. The Ethereum network has at times faced congestion problems, for example, congestion occurred during late 2017 in relation to Cryptokitties.[62] 

The "Metropolis Part 1: Byzantium" soft[citation needed] fork took effect on 16 October 2017, and included changes to reduce the complexity of the EVM and provide more flexibility for smart contract developers. Byzantium also added supports for zk-SNARKs (from Zcash), with the first zk-SNARK transaction occurring on testnet on September 19, 2017.[citation needed]
There are many ways you can plug into the Ethereum network, one of the easiest ways is to use its native Mist browser. Mist provides a user-friendly interface & digital wallet for users to trade & store Ether as well as write, manage, deploy and use smart contracts. Like web browsers give access and help people navigate the internet, Mist provides a portal into the world of decentralized blockchain applications.
Bitcoin, along with other cryptocurrencies, has been described as an economic bubble by at least eight Nobel Memorial Prize in Economic Sciences laureates, including Robert Shiller,[193] Joseph Stiglitz,[194] and Richard Thaler.[195][14] Noted Keyensian economist Paul Krugman wrote in his New York Times column criticizing bitcoin, calling it a bubble and a fraud;[196] and professor Nouriel Roubini of New York University called bitcoin the "mother of all bubbles."[197] Central bankers, including former Federal Reserve Chairman Alan Greenspan,[198] investors such as Warren Buffett,[199][200] and George Soros[201] have stated similar views, as have business executives such as Jamie Dimon and Jack Ma.[202]
Ethereum addresses are composed of the prefix "0x", a common identifier for hexadecimal, concatenated with the rightmost 20 bytes of the Keccak-256 hash (big endian) of the ECDSA public key (the curve used is the so called secp256k1, the same as Bitcoin). In hexadecimal, 2 digits represents a byte, meaning addresses contain 40 hexadecimal digits. An example of an Ethereum address is 0xb794F5eA0ba39494cE839613fffBA74279579268. Contract addresses are in the same format, however they are determined by sender and creation transaction nonce.[34] User accounts are indistinguishable from contract accounts given only an address for each and no blockchain data. Any valid Keccak-256 hash put into the described format is valid, even if it does not correspond to an account with a private key or a contract. This is unlike Bitcoin, which uses base58check to ensure that addresses are properly typed.
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