What is Bitcoin and the blockchain?
Get started here https://coinvault.wixsite.com/coins . You'll first need a wallet to store your coins cryptographically. Preferably a desktop or hard wallet described at the website. Then start accumulating coins. Listed are the more profitable sites that reward you with bitcoins. Also checkout Airdrop = a company giving away their alt coins for publicity.
It is borderless, permissionless, ID less, resistent to censorship, irreversible, fast and available 24/7, 365.
The only signifcant barrier to it is access to the internet.
"On 18 August 2008, the domain name "bitcoin.org" was registered. In November that year, a link to a paper authored by Satoshi Nakamoto titled Bitcoin: A Peer-to-Peer Electronic Cash System was posted to a cryptography mailing list. Nakamoto implemented the bitcoin software as open source code and released it in January 2009 on SourceForge.The identity of Nakamoto (a person or group) remains unknown.
In January 2009, the bitcoin network came into existence after Satoshi Nakamoto mined the first ever block on the chain, known as the genesis block. Embedded in the coinbase of this block was the following text:
The Times 03/Jan/2009 Chancellor on brink of second bailout for banks.
This note has been interpreted as both a timestamp of the genesis date and a derisive comment on the instability caused by fractional-reserve banking.
The receiver of the first bitcoin transaction was cypherpunk Hal Finney, who created the first reusable proof-of-work system (RPOW) in 2004. Finney downloaded the bitcoin software the day it was released, and received 10 bitcoins from Nakamoto. Other early cypherpunk supporters were Wei Dai, creator of bitcoin predecessor b-money, and Nick Szabo, creator of bitcoin predecessor bit gold." - Bitcoin From Wikipedia.
This very first transaction, which was the result of a newly mined bitcoin block (known as a ‘coinbase’ transaction), went to the following public key address: 1A1zP1eP5QGefi2DMPTfTL5SLmv7DivfNa
Only 21 million bitcoins will ever exist. As of Jan 2018 there was close to 4.3 million Bitcoins left that weren’t in circulation yet. It is estimated that 30% of those may be lost forever as a result of things like hard drive crashes, misplaced private keys and yes willful destruction.
"The mining reward halving occurs every 210,000 blocks. With blocks taking about 10 minutes on average to mine, halvings occur about every 4 years.
After 64 total halvings, there will be no more Bitcoins left to reward miners and all 21 million Bitcoins will be in circulation. This will occur sometime in 2140.
You may be wondering, “Without block rewards, what incentive do miners have to validate transactions?”
Miners receive more than just the block rewards when they create new blocks. They also earn the fees associated with each transaction. Transaction fees vary with the amount of network congestion and transaction size." - How many Bitcoins are left? January 3, 2018 by Steven Buchko
The BlockSay person X wants to send some coins to person Y. Person X with their private key makes an announcemet to the Network that they are sending coins to person Y's public address. A block containing a digital signature (person X's private key + public key), public timestamp and relevant information, then broadcast to all nodes in the network. A Node is any computer connected to the Network. A Miner is anyone/thing that controls a node. That block then gets worked on by the Network with the reward of cryptocurrency.
Bitcoin mining is the process of adding transaction records or blocks to Bitcoin's public ledger of past transactions. This ledger of past transactions is called the blockchain as it is a chain of blocks.
The Miners (are validators of the Network). They make available their computer's processing power to validate a transaction with the reward of bitcoin for solving any particular block. A Miner may also be rewarded in bitcoin with small transaction fees charged for the solving of a block. Each blockchain has its own rules for what is a valid transaction and is not a valid transaction, or a valid creation of a new block.
Usually the Node or Groups of Nodes with the highest hash rate / processing power wins out in solving a block. Hence a powerful computer with a high processing speed can control the processing of a block, but that block also has to be verified. A single hacker would have to possess that amount of processing power to maliciously change a transaction, and beat all other computers working on that block in verifying that that was a valid transaction and do so in short order.
Any single hacker would have to have the processing power to beat out the processing power of the thousands of computers/Nodes that may be working on the same single block at any one time. The hackers transaction would have to be verified against the other (thousands of) copies of the blockchain in the Network. Something like a Quantum (Super) Computer would be a gold mine to a hacker. Especially since everyones home computer is likely to be getting faster and faster as technology advances, hence the prospects for a sucessful hack potentially becomes more difficult with time.
Sources - How Does Blockchain Technology Work? by Nolan Bauerle
Quora.com - Blockchain (database) - Can blockchain technology be hacked? Aug 1 2017
The Blockchain. Why is it revolutionary to how the world will do business in the future?The blockchain, is a decentralized public ledger, a copy of which can be stored on anyones computer for all to scrutinize. It is an ever growing list of transactions, records, called blocks, which are linked and secured using cryptography. Each block typically contains a cryptographic hash of the previous block, a timestamp and transaction data. By design, a blockchain is inherently resistant to modification. Each block is verified in a timely fashion by multiple "Miners" (computers, machines connected to the Bitcoin Network consisting of millions of computers), that follow a specific protocol. It is resistent to hackers, although not 100% impossible to hack. Bitcoin was the first blockchain, but Ethereum, Litecoin, Dash Coin etc. have their own blockchains with their individual protocols/rules.
The RevolutionThe future is not necessarily with Bitcoin but instead with the blockchain technology/protocols and their various viable applications. There will be less need for a bank or any financial institution. Less need for approval from any government or state. All transactions are verified by the collective i.e. the Network on any particular blockchain. The blockchain can be applied to everyday activities like time stamping trademarks, copy righting songs or Art, purchasing merchadise across borders or even obtaining fiat currencies from other countries without the approval or any bank or government. Countries are however looking at the blockchain as a why of combating corruption as it pertains to recording contracts and other financial activities.
The blockchain in conjunction with a solid business plan is responsible for the slew of ICOs (Initial Coin Offerings). ICOs can be viewed as crowd funding for potentially viable companies or business plans. Again side stepping the venture capitalists, banks and financial institutions. The big wigs will no longer be the final gate keepers to funding a good idea.
As with all forms of investments, there will always be SCAMs. Always do your due diligence before throwing good money behind a bad idea or a too good to be true story. Approach them as you would when investing in stocks. Note carefully that the coins issued from these ICOs may not be equivalent to the stocks in a Stock Market. Stocks buy you part ownership of a company. Coins confer benefits that may or may not be defined in the company's 'white paper', the equivalent to the 'propectus' of a company in the stock market. These coins may or may not convey ownership, more likely not, so read the 'white paper'
These coins have zero intrinsic value, like gold, diamonds or fiat currencies it is the Community that gives it value.