Is Blockchain a Linked List?

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A blockchain is a collection of transaction blocks that is finite, organized, and back-linked. If you want to learn about Blockchain thoroughly, you must first understand linked lists. A linked list is a set of linear data structures linked together by links. Each link in the blockchain is connected to its corresponding link.

If this sounds confusing to you, don’t worry. This article will break down the similarities and differences between blockchains and linked lists so you get a clear understanding of both.

What Is a Linked List?

A linked list is a set of linear data structures linked together by links. Each link in the linked list is connected to its corresponding link. Every node stores data called an element. In a linked list, each node has at least two parts:

  1. The first part contains Data.
  2. The second part contains a Pointer to the next node.

A linked list does not store the elements at contiguous memory. A pointer represents the first node of the linked list, and the first node is called a Head. The value of the head is NULL if the linked list is empty. Linked plans can increase in size, and inserting and deleting elements from them is simple since we need to adjust the pointers of the previous and next elements to insert or remove an element.

Linked lists are generally used to create file systems and hash tables.

What Is a Blockchain?

A blockchain is a network of peer-to-peer nodes that stores transactional records, also known as blocks; in many databases, it is referred to as chains.

This type of storage is generally called a digital ledger. Any transaction in this ledger is found with the owners’ digital signature, verifying the transaction and protecting it from tampering. As a result, the data in the digital ledger is highly stable.

Data is organized in a blockchain by dividing it into subsets known as blocks. The notes on the linked list are similar to blocks. There are several elements in each block, and they are divided into a block header and its transactions. The transactions in a block account for most of the data. The block header includes important information about each block, such as the timestamp and the block height.

A digital ledger is like a Google spreadsheet that is exchanged between multiple devices in a network. It stores transactional records based on the actual purchase. The main advantage here is that everyone can view the data, but nobody can manipulate it.

A block consists of a header and transactions. A Merkle tree is used to generate a 256-bit summary of all transactions included in the block header.

A transaction is a message to the network that specifies which unspent transaction outputs are being spent and which new UTXOs are being created.

Differences Between Blockchains and Linked Lists

Blockchain Linked List
In a blockchain, the reference is cryptographically encrypted and tamper-evident. The Pointer is a linked list that can be frequently changed without disturbing the data integrity.
A hash function is used to define a previous block in the blockchain. Linked lists use a pointer function to define a previous node.
As a structure, a blockchain is far more complex. A linked list is a structural way of storing and organizing data.
Blocks are available for storing all data related to transactions. These blocks chain link with their parent hash with the unique hash number. The complete list in the linked list works as a chain, so it is easy to trace the previous node.


Tampering and data manipulation are almost impossible in a blockchain. A linked list is a simple list where data manipulations can happen.
A blockchain is a completely functioning autonomous system. The linked list lacks data validations which ensure the integrity of the linked list.
Deleting data in a blockchain is impossible. A linked list can delete data.
Rearranging blocks in a blockchain is possible. Rearranging nodes is not possible in a linked list.

Are Blockchains Related to Linked Lists?

Blockchains can be represented as a singly linked list. While they have a close structure to that of a linked list, they are not a linked list. A linked list is a programming language data structure. In contrast, a blockchain is an incredibly high-end technology. Blockchains have a hash function, whereas linked list have a pointer function. Each block contains a hash of the parent block or previous block and has a unique number, which can be viewed as a pointer to the last block. In a blockchain, each transaction is stored in one Merkle Tree. So yes, blockchains do have several characteristics in common with a linked list data structure.

Final Verdict: Blockchains vs. Linked Lists

To answer the original question this article put forward, no, a blockchain isn’t a linked list. While they do have things in common, such as the data in a blockchain being divided into blocks similar to that of a linked list, they are still separate entities. Every block in a blockchain is connected to the previous block via a cryptographically secure connection. On the other hand, a single linked list is a data structure for storing data in which a pointer connects the nodes. In the case of blockchains, Merkle trees are used to store data in each block. Merkle trees, in turn, use the hash to connect each block. Furthermore, the cost of creating and maintaining a public blockchain is very high.

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What are blockchain risks?
increase in implementation of blockchain technology, there is a rise in the risks associated with blockchain. Therefore, it is crucial to identify various blockchain risks and mitigate them.
Four significant blockchain risks are:

  1. Vendor Risk
  2. Endpoint Security Risk
  3. Lack of Standards and Regulations
  4. Cryptocurrency Risk

Read more: Top 4 Blockchain Risks a CIO Should Know

What is meant by DLT?
Distributed Ledger Technology or DLT, is a digital system that allows participants to simultaneously access, validate and update a record globally. The records in DLT are immutable and cannot be deleted. No single entity (individual or group) has the entire authority over the transactions and processes, it is distributed among the participants.

Read more: Distributed Ledger Technology – How Does it Work and How it Affects Blockchain?

What is meant by smart contracts in blockchain?
In blockchain, smart contracts are self-executing automated applications or lines of code that operate on decentralized network of blockchain. They are used to make financial transactions transparent and efficient as it eliminates administrative authority to control the ledger. It allows complex transaction processes between multiple participants.

Read more: What is a Smart Contract in Blockchain?

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