What is Blockchain? The Tech Powering Cryptocurrencies

• A blockchain is a shared ledger maintained by a network, not a single company or database.
• Blocks are linked together so the record is hard to alter after the fact, which supports tamper resistance.
• “Tamper-resistant” means changing past records typically requires redoing work or gaining control of a large portion of the network, which is difficult on major public blockchains.
• Blockchain technology is legal to use and build on in Canada. However, crypto assets (which often run on blockchains) are high-risk and are not legal tender in Canada.

Key takeaways: A blockchain is a shared ledger that is designed to be secure, decentralized, and append-only. It lets users verify data and transactions without a central authority. Blockchain powers crypto networks like Bitcoin and Ethereum, but it also has broader applications.

• Blockchain: A distributed ledger where transactions or data are grouped into blocks.
• Node: A computer that helps maintain and validate the blockchain ledger.
• Block: A bundle of verified transactions or data entries added to the chain.
• Private Key: The secret information used to authorize transactions.
• Consensus: The method the network uses to agree on which transactions are valid.

A blockchain is a decentralized database where all entries are public and secured by cryptography. Public blockchains make ledger data easily visible, while private or permissioned blockchains restrict who can read or write data. When people reference “blockchain,” it means two related things:

• The blockchain network: a group of nodes (computers) that maintain and validate the shared ledger.
• The blockchain data: the ledger itself, made up of linked blocks of information.

A crypto wallet is a tool that lets users access and control their assets on a blockchain. Most new users don’t understand that a wallet itself doesn’t store data or coins inside it. Instead, a wallet lets users manage assets that are recorded on the blockchain.

Crypto wallets are used to interact with networks (like Bitcoin or Ethereum) or other applications.

Blockchain technology is legal to use and build on in Canada; regulatory requirements usually apply to specific activities like trading, custody, or issuing investment products.

Canadian regulators have cautioned that blockchain-based assets (i.e., crypto) are high-risk, and Canadians who choose to trade crypto generally look for regulator-aligned services with clear disclosures and security practices. Crypto assets are not covered by the Canadian Investor Protection Fund (CIPF) or deposit insurance. Ndax operates within Canadian regulatory requirements. Canadians can check whether a crypto platform is authorised to do business with Canadians using the Canadian Securities Administrators’ list.

Public blockchains are designed with security features. However, risks still exist when using apps, trading tokens, or managing assets. When evaluating safety, it is important to separate technology risk from user and platform risk.

Blockchain records are hard to tamper with, but users could still fall victim to fraud, lost passwords, or insecure platforms. For most users, the main risks are not related to the blockchain ledger itself. This includes fraud, phishing, lost recovery phrases, and using unregistered or insecure platforms. 

Using a blockchain is not always free. Many networks charge transaction fees, while some activity can be free depending on the network and how it is used.

Ndax charges a flat trading fee of 0.20% on all buy and sell orders. Network fees vary by blockchain and method.  Trading fees charged by a platform are separate from blockchain network fees, which are paid to validators or miners to process transactions.

Blockchains work by allowing many independent computers to agree on a shared history of data or transactions. There are several components required to understand how a blockchain operates.

Transactions and confirmations
When a transaction is submitted (such as a user request) to a blockchain, it is verified by the network. Once included in a block, it receives confirmations. More confirmations mean higher confidence that the data is final and cannot be reversed.

Keys and control
Control over blockchain-based assets is determined by private keys. Users can either manage their own keys through a self-custody wallet, or use a platform that holds keys on their behalf.

Consensus and validation
Blockchains use consensus mechanisms to validate new blocks. Popular methods include proof of work and proof of stake. These systems are designed to help secure the network and reduce the risk of fraud.

Blockchain’s use case
Blockchain technology is used to record any type of information. Examples include cryptocurrency payments, non-fungible tokens (NFTs), supply chain tracking, and digital identity systems.

Blockchain is also used in decentralized finance (DeFi) applications, where users can lend, borrow, or trade crypto assets without traditional banks.
 

Blockchain technology is vital in creating trust and transparency in a relatively new system without relying on a central authority. That makes it useful for recording and verifying data across industries.

The most common reasons why users value blockchain technology include:

• Transparency: Records are public and verifiable.
• Security: Data is protected by cryptography and consensus.
• Decentralization: No single person or entity controls the network.
• Immutability: Once a transaction is confirmed, data cannot easily be changed.

Skeptics would point to higher energy use (on some networks), complexity, and the risk of scams or human error.
 

Most public blockchains are pseudonymous: addresses are public, and identities can sometimes be linked through real-world activity.

In some cases, real-world activity can be linked to blockchain addresses. A practical takeaway for beginners is to operate under the assumption that addresses and transaction details are potentially traceable.

These are practical security habits many users follow to reduce avoidable mistakes for everyday users:

• Use strong account security, including unique passwords and 2FA.
• Be cautious of phishing and impersonation attempts.
• Avoid address reuse where possible.
• Keep wallet software and devices updated.
• Understand custody trade-offs.
   

Is blockchain legal in Canada?
Yes. Blockchain technology is legal to use and build on in Canada.

Can I invest in blockchain?
Blockchain refers to a technology. Users can gain exposure to blockchain through crypto assets or blockchain-related stocks or funds. These investments are not guaranteed and carry risk.

Who invented blockchain?
The first major blockchain was created in 2009 by the anonymous person or group known as Satoshi Nakamoto. It was used to launch Bitcoin.

Can I use blockchain without buying crypto?
Yes, although use cases are limited. Some apps use blockchain for record-keeping or verification without requiring users to buy tokens.

Is blockchain anonymous?
No. Most blockchains are open and transparent. Transactions are pseudonymous but could be linked to real-world identities over time.

Is data on a blockchain permanent?
Yes. Once data is added to a blockchain, it is hard to change. This is part of what makes the system secure.

Are blockchain apps regulated in Canada?
Apps that deal with financial services or crypto ownership must register with regulators. Not all blockchain projects are subject to the same rules.