Ethereum aims at providing a Turing-complete programming language for scripts with which smart contracts can be written. Such a script (or smart contract) is then stored in the blockchain.
The script can then be executed in an Ethereum virtual machine (EVM).
Solidity
The high level programming language to write such scripts is called Solidity.
Gas
When a script is executed, it needs »gas« for each instruction. When the gas is exhausted, the script stops. This makes sure that a script does not run indefinitly long.
Gas is paid for with Ether, the currency of Ehtereum.
GHOST
GHOST is the protocoll to determine the consensus branch.
Smart contracts
Ehtereum's smart contracts are written in a stack-based byte code language.
The language is turing-complete, unlike Bitcoin's.
A prominent high language to create the byte code is Solidity.
Misc
A token represents a fungible good which is countable and whose ownership is transferable.
An oracle is a contract that is used to query externa data.
Creating a random number is not a trivial task for a contract because all nodes must generate the same value when executing the contract.
TODO
The Melon protocol is a blockchain protocol for digital asset management on the Ethereum platform. It enables participants to set up, manage and invest in digital asset management strategies in an open, competetitive and decentralised manner.