Ethereum enables developers to build and deploy decentralized applications. A decentralized application or Dapp serve some particular purpose to its users. Bitcoin, for example, is a Dapp that provides its users with a peer to peer electronic cash system that enables online Bitcoin payments. Because decentralized applications are made up of code that runs on a blockchain network, they are not controlled by any individual or central entity.

Other projects like OmiseGo are now building on top of Ethereum, using this as a parent chain and providing scaling solutions such as Plasma to really push the boundaries of what is currently possible with Ethereum, other such projects like Raiden are also important in the long run as they allow transaction speeds to ramp up, whilst there are a range of other projects to speed up bitcoin exchanges and bitcoin applications such as the lightning network, Ethereum too will be using sharding along with other side chain projects to allow for a much more efficient and expansive system for everyone to participate.

Just when it seemed that things couldn’t get any worse, they did. As mining costs were rising, bitcoin prices began to dive. The cryptocurrency was getting hammered by a string of scams, thefts and regulatory bans, along with a lot of infighting among the mining community over things like optimal block size. Through 2015, bitcoin prices hovered in the low hundreds. Margins grew so thin—and, in fact, occasionally went negative—that miners had to spend their coins as soon as they mined them to pay their power bills. Things eventually got so grim that Carlson had to dig into his precious reserves and liquidate “all my little stacks of bitcoin,” he recalls, ruefully. “To save the business, we sold it all.”
Either a GPU (graphics processing unit) miner or an application-specific integrated circuit (ASIC) miner. These can run from $500 to the tens of thousands. Some miners--particularly Ethereum miners--buy individual graphics cards (GPUs) as a low-cost way to cobble together mining operations. The photo below is a makeshift, home-made mining machine. The graphics cards are those rectangular blocks with whirring circles. Note the sandwich twist-ties holding the graphics cards to the metal pole. This is probably not the most efficient way to mine, and as you can guess, many miners are in it as much for the fun and challenge as for the money.

The following Terms and Conditions (“Terms”) govern the use of the Ethereum open source software platform (“Ethereum Platform”). Prior to any use of the Ethereum Platform, the User confirms to understand and expressly agrees to all of the Terms. All capitalized terms in this agreement will be given the same effect and meaning as in the Terms. The group of developers and other personnel that is now, or will be, employed by, or contracted with, Stiftung Ethereum (“Stiftung Ethereum”) is termed the “Ethereum Team.” The Platform will be developed by persons and entities who support Ethereum, including both volunteers and developers who are paid by nonprofit entities interested in supporting the Ethereum Platform.