The Genesis Block
Early versions of the Genesis block on the blockchain were Block 1, but in the modern versions, it is block 0. Most of the times the Genesis block is hardcoded into the software of the applications that utilize it’s blockchain. This new block, also known as block 0, reference back to a previous block. The chain of blocks, built on this block, holds millions of transactions. The Genesis block is the beginning and every blockchain and a blockchain needs to have it.
Out of the chain of blocks from the Genesis block, you can have a hard or a soft fork. The fork is a new blockchain with new software which forms out of the first chain. An example of it is the chain configuration, and the level of difficulty to mine the blocks.
Nine years back, on the 3rd of January 2009 Satoshi Nakamoto mined the Genesis block on the Bitcoin network. This digital currencencies which are created are decentralized with not middleman, to stored and spent Bitcoins or Altcoins (Altcoins are coins which followed after Bitcoin), electronically. This was the start of cryptocurrencies.
The miners of the Genesis block or the 0 blocks is probably the founders of Bitcoin and Ethereum (Satoshi Nakamoto, Bitcoin or Vitalik Buterin, Ethereum).
The 0 block is decentralized and secure like the whole chain. The genesis block will never or can’t be deleted or the blockchain. This block can handle 7 transactions per second. Every ten minutes or so is a 1MB block been added on the blockchain by miners.