Consider the following scenario:
Two Generals are at war and planning to strike the enemy. In order to initiate the strike, General Hodl must get a message to General Fud to confirm that his troops are ready to attack. Problem is, the only way General Hodl can send the message is by horseback messenger. The only route between Hodl and Fud is straight through enemy territory:
Now consider that once General Fud receives the message, he must reply with a messenger of his own to confirm his troops are ready. The area between Hodl and Fud is infested with enemy troops. What if Fud never gets Hodl's message? Even worse, what if the enemies intercept the message and send a counterfeit message to Fud to misdirect him? They could even pull some Cersei Lannister type shit and have their maester develop a topical derivative of the Long Farewell, applying it to the message and killing the enemy General as soon as he touches it.
This thought experiment is known as the Two Generals' Problem. In computing, this idea is meant to illustrate the challenges associated with coordinating an action over an unreliable link. According to Wikipedia, it was the first computer communication problem which was proved to be unsolvable.
Basically, what this means is that instead of trying to send the message directly to General Fud, Hodl freely sends the message to everyone. The only way anyone can read the message is to "unlock" it with a specific private key which is associated with the public key or "address" of the recipient. In this case, General Fud. Since the only identifying piece of information about the desired destination of the message is its public key, nobody knows who the message is for (except for Fud, who knows his own public and private key). Nobody can doctor the message since it is freely available for anyone to view. Copies of the message exist everywhere, and the "true" contents and destination of the message are determined through mutual network consensus. Hodl is free to securely send an immutable message to Fud, allowing the blue guys to win the war!
Want to buy Bitcoin?
The best place to buy Bitcoin (BTC), Litecoin (LTC), and Ethereum (ETH) is on Coinbase. Coinbase secures most of it's assets in cold storage offline and all online funds are insured. This is by far the safest way to buy and store online.
Securing your BTC or other Cryptos:
While Coinbase is the safest option for purchasing cryptoassets with fiat currencies online, it is best to own your own wallets by storing your assets in a secure hardware wallet. I recommend the Ledger Nano S. This wallet is versatile, secure, and very easy to use. This is the wallet I use to secure the majority of my crypto holdings.
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