Merge pull request #285 from danielweinmann/patch-1

Fixes typo on what-is-ethereum.rst

source/introduction/what-is-ethereum.rst

@@ -47,7 +47,7 @@ Contract accounts only perform an operation when instructed to do so by an EOA.
 
 Like in Bitcoin, users must pay small transaction fees to the network. This protects the Ethereum blockchain from frivolous or malicious computational tasks, like DDoS attacks or infinite loops. The sender of a transaction must pay for each step of the "program" they activated, including computation and memory storage.  These fees are paid in amounts of Ethereum's native value-token, ether.
 
-These transaction fees are collected by the nodes that validate the network. These "miners" are nodes in the Ethereum network that receive, propogate, verify, and execute transactions. The miners then group the transactions – which include many updates to the "state" of accounts in the Ethereum blockchain – into what are called "blocks", and miners then compete with one another for *their* block to be the next one to be added to the blockchain. Miners are rewarded with ether for each successful block they mine. This provides the economic incentive for people to dedicate hardware and electricity to the Ethereum network.
+These transaction fees are collected by the nodes that validate the network. These "miners" are nodes in the Ethereum network that receive, propagate, verify, and execute transactions. The miners then group the transactions – which include many updates to the "state" of accounts in the Ethereum blockchain – into what are called "blocks", and miners then compete with one another for *their* block to be the next one to be added to the blockchain. Miners are rewarded with ether for each successful block they mine. This provides the economic incentive for people to dedicate hardware and electricity to the Ethereum network.
 
 Just as in the Bitcoin network, miners are tasked with solving a complex mathematical problem in order to successfully "mine" a block. This is known as a "Proof of Work". Any computational problem that requires orders of magnitude more resources to solve algorithmically than it takes to verify the solution is a good candidate for proof of work. In order to discourage centralisation due to the use of specialised hardware (e.g. ASICs), as has occurred in the Bitcoin network, Ethereum chose a memory-hard computational problem. If the problem requires memory as well as CPU, the ideal hardware is in fact the general computer. This makes Ethereum's Proof of Work ASIC-resistant, allowing a more decentralized distribution of security than blockchains whose mining is dominated by specialized hardware, like Bitcoin.