Learn / Lesson 4

What is cryptocurrency?

A cryptocurrency is digital money that exists only on a computer network. There are no coins or notes to hold. Instead, ownership is recorded on a blockchain, and the rules for how it works are enforced by software and mathematics rather than by a bank or government.

The "crypto" in the name comes from cryptography, the branch of maths used to secure messages and prove identity. It is what lets you prove that a coin is yours, and stops anyone else from spending it, without a bank checking on your behalf.

How ownership works

When you hold cryptocurrency, you do not keep files on your phone. What you hold is a pair of digital keys:

• A public key (or address), which works like an account number. You can share it so people can send you funds.
• A private key, which works like a password that signs your transactions. Whoever has it controls the funds.

These keys are managed by a wallet, which is an app or device. Your private key is often backed up as a seed phrase, a list of 12 or 24 ordinary words. If you lose your phone, those words can restore your wallet. If someone else finds them, they can empty it.

This is the biggest difference from a bank account. A bank can reset your password if you forget it. With self-custody crypto, there is no help desk. You are your own bank, with all the freedom and all the responsibility that brings.

Coins and tokens

People use "coin" and "token" loosely, but they mean slightly different things:

• Coins run on their own blockchain. Bitcoin (BTC), ether (ETH) and SOL are coins.
• Tokens are built on top of another blockchain, usually using smart contracts. Thousands of tokens exist on Ethereum and Solana, from stablecoins to community tokens to game items.

As of the mid-2020s there are well over ten thousand cryptocurrencies. Most will never matter. Many have already disappeared. A small number have lasted years and built real communities and uses.

What people do with it

• Send money. Transfers can reach another country in minutes, at any hour, often for a lower fee than a traditional wire.
• Save or hold. Some people keep a small amount as a long-term bet. Others use stablecoins, which aim to track the US dollar, as a way to hold dollar value.
• Trade. Prices change every second, and some people try to profit from the swings. Most beginners who trade lose money.
• Use apps. On networks like Ethereum, cryptocurrency pays for lending, games, digital collectibles and more.

Where the value comes from

Why would anyone pay for something that exists only as data? The honest answer is the same reason people pay for many things: because others are willing to pay for it too. Several factors feed that willingness:

• Scarcity. Some cryptocurrencies have a limited supply. Bitcoin's 21 million cap is the best-known example.
• Usefulness. A network that people actually use needs its coin to pay fees, which creates demand.
• Trust in the system. People value a network that has run for years without being hacked or shut down.
• Belief and speculation. Much of the price at any moment reflects what people hope it will be worth later. That is why prices can jump and crash so quickly.

No government or company guarantees the price. That is very different from your bank balance, which in Trinidad and Tobago is backed by the banking system and the TT dollar.

How it differs from the money in your bank

• No central issuer. No central bank decides how much exists. The rules are in the software.
• Always open. The networks run every hour of every day, including holidays.
• Irreversible. A sent payment cannot be recalled. If you pay the wrong address or get tricked, the money is gone.
• Not legal tender. In Trinidad and Tobago, regulators have long said virtual currencies are not legal tender. Shops are not required to accept them.

The local picture

Trinidad and Tobago regulators, including the Central Bank, the Securities and Exchange Commission and the Financial Intelligence Unit, issued a joint warning in January 2019 about the risks of virtual currencies, including schemes that promise high returns. In December 2025 the Virtual Assets and Virtual Asset Service Providers Act, 2025 came into effect. Until 31 December 2026 it temporarily prohibits virtual asset activities as a business in or from Trinidad and Tobago, unless the TTSEC has approved the business through its Regulatory Sandbox. The TTSEC says the temporary ban does not cover individuals using virtual assets for personal transactions such as buying goods and services. Rules are still developing, so check current guidance before you act, and see our Trinidad and Tobago rules lesson for more.

Keep in mind

• Prices can fall by half or more in weeks. Only ever use money you can afford to lose.
• Be very wary of anyone promising guaranteed returns. That is the most common sign of a scam.
• Never share your seed phrase with anyone, for any reason. Real support staff will never ask for it.
• Double-check every address before sending. Transactions cannot be undone.
• None of this is financial advice. This site teaches how things work so you can decide for yourself.

Common mistakes beginners make

Treating a coin's low price as a bargain. A cheap price per coin says nothing about value. The next lessons on market cap explain why.

Storing the seed phrase in a photo or message. Screenshots and chat messages get backed up to the cloud, where they can be stolen. Write it on paper and keep it somewhere safe and private.

Skipping a test payment. Always send a small test amount first when paying a new address. A mistyped address cannot be fixed afterwards.

Trusting strangers who contact you first. Unexpected messages offering investments, "mentors" or "trading bots" are a leading source of scams, including in the Caribbean.

Try it yourself

Write down in two columns what you would want from money: for example, easy to spend in Trinidad and Tobago, stable in value, safe from theft, and accepted everywhere. Then mark whether cash, a bank balance and a cryptocurrency each does well or poorly on each point. You will likely find that each has strengths and weaknesses, which is the key lesson of this module.

Quick questions

Is cryptocurrency the same as a bank balance? No. A bank balance is a claim on a regulated bank, and bank deposits in Trinidad and Tobago are covered by deposit insurance up to a limit. Cryptocurrency held in your own wallet is not a claim on anyone, and no insurance scheme replaces it if it is lost or stolen.

Do I need to buy a whole bitcoin? No. Cryptocurrencies can be split into very small parts. A bitcoin can be divided down to eight decimal places, so a person can hold a tiny fraction of one.

Can cryptocurrency be stolen? Yes. Thieves use fake websites, fake support staff and fake investment offers, and exchanges have been hacked. Losing your seed phrase can also mean losing access for good. That is why the safety lessons matter as much as the technology lessons.

Key terms from this lesson

• Cryptocurrency — digital money secured by cryptography and recorded on a blockchain.
• Wallet — an app or device that holds your keys and lets you send and receive.
• Private key / seed phrase — the secret that proves you own your funds.
• Coin — a cryptocurrency with its own blockchain.
• Token — a cryptocurrency built on another blockchain.
• Stablecoin — a token designed to hold a steady value, such as one US dollar.

Sources and credits

Local context: the January 2019 joint advisory from the Central Bank, TTSEC and FIU, summarised in the Central Bank's 2023 speech, and the TTSEC notice on the 2025 Act as reported by the Trinidad Express. Rules change, so check current guidance. Law: TTSEC fact sheet on the 2025 Act. Education only, not financial advice.

Module quiz

3 questions. Tap an answer to see if you are right and why. Get 2 right to complete the module.

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