The genesis block is the zero, original block of any blockchain. The chain begins from it: all subsequent blocks reference their predecessors all the way back to this first link. The appearance of the genesis block marks the launch of a new cryptocurrency, since it is what sets the starting state of the network and the rules by which it will develop.

Unlike ordinary blocks, the genesis block does not reference a previous one — it simply has no predecessor. Often its parameters are written directly into the protocol code by the network's creators. Because each new block is cryptographically linked to the previous one, the genesis block becomes an immutable foundation: an attempt to change it would require rewriting the entire subsequent chain.

Features of the genesis block

• it is the first block of the network, with no predecessor;
• it sets the starting parameters and operating rules of the blockchain;
• it serves as an immutable reference point for the entire chain.

The genesis block has not only technical but also symbolic significance: it marks the moment of the network's birth and often contains special marks left by its creators.