Gwei

Basics

• 1 gwei, also known as a nanoether, is equal to 0.000000001 ETH.
• From Token Tuesdays (25-9-2019):

"Ethereum leverages a native currency, Ether, to execute transactions on the network. Whenever you hear the term “gas”, this simply refers to a very small amount of Ether that is consumed to reward miners for processing (or validating) your transaction. Units of ether are denoted in gwei with 1,000,000,000 wei being equivalent to 1 ether."

• From this article by CoinDesk (28-9-2019):

"In order to prevent network congestion, miners on the ethereum network have recently responded to the surge in transaction activity by increasing ethereum’s “gas limit.”

Stepping back, the cost to send a transaction on the ethereum network is called gas and paid in fractions of ETH called gwei. For every block processed on the ethereum blockchain, there is a limit to the overall amount of gas that can be collected by miners.

In short, a higher gas limit means that a higher number of transactions can be included in a block. On Sept. 19, ethereum miners collectively raised network gas limits from 8 million to 10 million gwei. Ethereum blocks are now effectively 25 percent larger – allowing for larger transaction processing loads."