# Block Creates a new block object **Parameters** - `data` **([Array](https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Global_Objects/Array) \| [Buffer](https://nodejs.org/api/buffer.html) \| [Object](https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Global_Objects/Object))** **Properties** - `header` **Header** the block's header - `uncleList` **[Array](https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Global_Objects/Array)<Header>** an array of uncle headers - `raw` **[Array](https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Global_Objects/Array)<[Buffer](https://nodejs.org/api/buffer.html)>** an array of buffers containing the raw blocks. ## hash Produces a hash the RLP of the block ## isGenisis Determines if a given block is the genesis block Returns **any** Boolean ## setGenesisParams turns the block in to the canonical genesis block ## serialize Produces a serialization of the block. **Parameters** - `rlpEncode` **[Boolean](https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Global_Objects/Boolean)** whether to rlp encode the block or not ## genTxTrie Generate transaction trie. The tx trie must be generated before the transaction trie can be validated with `validateTransactionTrie` **Parameters** - `cb` **[Function](https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Statements/function)** the callback ## validateTransactionTrie Validates the transaction trie Returns **[Boolean](https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Global_Objects/Boolean)** ## validateTransactions Validates the transactions **Parameters** - `stringError` **[Boolean](https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Global_Objects/Boolean)?** whether to return a string with a dscription of why the validation failed or return a Bloolean (optional, default `false`) Returns **[Boolean](https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Global_Objects/Boolean)** ## validate Validates the entire block. Returns a string to the callback if block is invalid **Parameters** - `blockChain` **BlockChain** the blockchain that this block wants to be part of - `cb` **[Function](https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Statements/function)** the callback which is given a `String` if the block is not valid ## validateUncleHash Validates the uncle's hash Returns **[Boolean](https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Global_Objects/Boolean)** ## validateUncles Validates the uncles that are in the block if any. Returns a string to the callback if uncles are invalid **Parameters** - `blockChaina` **Blockchain** an instance of the Blockchain - `cb` **[Function](https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Statements/function)** the callback - `blockChain` ## toJSON Converts the block toJSON **Parameters** - `labeled` **Bool** whether to create an labeled object or an array Returns **[Object](https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Global_Objects/Object)**