Once again, Bitcoin is dangerously close to the local lows. Since June, we have many times seen that bulls stand up for protection of the benchmark of the cryptocurrency on the falls to around $6100. Meanwhile, reversals to decline on the BTCUSD pair are happening on low levels. Last week, the reach of just $6500 became a turning point to the next reversal. It ...

Transactions that occur on the network such as, “Alice sends 10 bitcoins to Bob”, are collected by a miner and bundled up into a block. The miner then verifies that all transactions in the block are valid, as if he attempts to submit a block with an invalid transaction, the block will be rejected. An example of an invalid transaction would be Alice sending 10 Bitcoins to Bob, even though she does not have 10 Bitcoins to send.
Stellar’s goal is providing a fast, efficient, and inexpensive service to individuals for cross-border payments. Unlike XRP, Stellar is geared to individuals, not large institutions. Companies like Paypal currently dominate the online payment sector and charge around 5% in fees per transaction. In contrast, Stellar offers 5 second transaction speeds and extremely low fees (e.g. the Tempo remittances dApp running on the Stellar blockchain can process 600,000 transactions for 0.01 USD). Importantly, Stellar is it does not use proof of work verification, which means it doesn’t have to deal with the energy consumption issue plaguing Bitcoin (instead of PoW it uses the Stellar Consensus Protocol). Finally, Stellar has established several partnerships with large tech companies, including IBM. I think Stellar represents a solid investment.

Thanks to some great partnerships we have established with hardware producers, as well as to our large scale purchases, we get better prices on our employed technology. This means we buy the hardware cheaper than the market price. What also bears great importance, considering the maintenance costs, is the storage of the miners: we have several farms around the globe, and each location was chosen to fulfill two important criteria: cheap electricity supply and little or no need for cooling.
The above list shows that, fundamentally, yes, anyone can mine cryptocurrencies; however, you must have a keen interest in mining, as well as an appetite to constantly learn and keep up to date on any technology changes. You also have to have the initial budget to be able to set up everything that is required. So, although, technically anyone can mine, realistically, it is not suited to everyone.
In Bitcoin terms, simultaneous answers occur frequently, but at the end of the day there can only be one winning answer. When multiple simultaneous answers are presented that are equal to or less than the target number, the Bitcoin network will decide by a simple majority--51%--which miner to honour. Typically, it is the miner who has done the most work, i.e. verifies the most transactions. The losing block then becomes an "orphan block." 
Cryptocurrencies are a potential tool to evade economic sanctions for example against Russia, Iran, or Venezuela. In April 2018, Russian and Iranian economic representatives met to discuss how to bypass the global SWIFT system through decentralized blockchain technology.[56] Russia also secretly supported Venezuela with the creation of the petro (El Petro), a national cryptocurrency initiated by the Maduro government to obtain valuable oil revenues by circumventing US sanctions.
The blockchain is like a collection of pages on that ledger. Each “page” is called a block, and contains multiple transactions. Whenever a block is filled up and a new transaction comes in, that transaction creates a new block with a link to the previous block. This new block is then appended to the blockchain. Once a transaction is written into the block, it becomes immutable: it cannot be edited or deleted.
Many users forgot one of the most important features of Bitcoin—controlling your own money—and left more than 800,000 bitcoins in Gox accounts. In February 2014, Gox halted withdrawals and customers were unable to withdrawal their funds. The company’s CEO claimed that the majority of bitcoins were lost due to a bug in the Bitcoin software. Customers still have not received any of their funds from Gox accounts.

Bitcoin solves the so called ‘’double spending problem’’ present with digital goods. For example, if I have an mp3 file or an ebook on my computer, I can freely copy that file a thousand times and send it to a thousand different people. For a digital currency, the possibility for unlimited copying would mean a quick hyperinflationary death. Bitcoin solves this by maintaining a peer to peer network and recording each transaction in a public ledger called the block chain. Say I send 1 bitcoin from my bitcoin address to my friend John. The bitcoin network records that transaction in the block chain and I no longer have possession of that bitcoin. The coin ‘’moved’’ from my bitcoin wallet to John’s wallet.