Ethereum is a decentralized community of desktops with two fundamental capabilities.
They are: blockchain that can report transactions, and a virtual machine that can make intelligent contracts.
Because of these two functions, Ethereum is capable to assistance decentralized applications (DApps). These DApps are built on the current Ethereum blockchain, piggybacking off of its underlying technology. In return, Ethereum rates builders for the computing energy in their community, which can only be compensated in Ether, the only inter-platform forex.
Dependent on its function, DAPPs could possibly produce ERC-20 tokens to function as a currency, a share in the enterprise, for points in a loyalty software, or even evidence of possession, say, of an volume of gold or the deed to a dwelling.