Ethereum can be used as a platform towards another projects. To give you an idea regarding that, if you know Binance Coin. It's a known altcoin today which has started itself on Ethereum Smart Contract. And when they've became stable, they've made their own chain/mainnet.
It's like a project that you can create another project through it. And with the latest updates about it is the 2.0. Which makes it become a proof of stake coin, where transactions will no longer be confirmed or mined by GPUs but by wallets that has the eligible amount of Ethereum.