What Is an Uncle Block (Ommer Block)?
An uncle block, also known as an ommer block, is a type of transaction in the Ethereum blockchain. It occurs when two miners find blocks at nearly the same time and one miner’s block becomes orphaned or rejected by the network. This can happen due to latency issues or other technical problems that prevent both blocks from being accepted simultaneously. When this happens, all transactions included in the rejected block are not added to the chain and become “stuck” until they are mined again in another valid block.
The purpose of an uncle/ommer block is to reward miners for their work even if their blocks do not get accepted into the main chain. Miners who successfully mine these types of blocks receive rewards based on how deep it was found within the blockchain (i.e., how many previous blocks had been mined before it). These rewards help incentivize miners to continue mining despite potential losses caused by failed attempts at finding new blocks. Additionally, uncle/ommer blocks provide additional security for users since any malicious activity contained within them will be discarded instead of propagating through the entire network like regular confirmed transactions would do otherwise.