The blockchain is a distributed ledger-based computational paradigm in which the transactions of the entire network are stored and maintained. It works under a bitcoin protocol and cryptocurrency model. The blockchain model offers a secure decentralized infrastructure to trust evaluation and maintenance. It is a disruptive solution for the issues of centralized security and privacy of the VANET system. In a trust-based VANET security system, the blockchain is used to store the trustworthiness of nodes accessible to the nodes at any time owing to the advantage of the public blockchain. The first block or genesis block is the birth of the blockchain, which is common to all nodes. The blockchain comprises a sequence of blocks encrypted with cryptographic hashes in which each block holds the data of its preceding blocks. Also, the irreversible trust blocks enhance the trust estimation accuracy and maximize the overall VANET performance.