What Is Bitcoin? A Beginner’s Guide

Throughout the history of money, financial transactions have almost always required intermediaries like banks, governments, and payment processors. These middlemen control the flow of value, set the rules, and impose fees. This power allows them to freeze accounts, devalue currency through inflation, or deny transactions entirely.

This model was challenged in 2008 when a pseudonymous entity, Satoshi Nakamoto, published a whitepaper introducing Bitcoin. As the world’s first decentralized digital currency, Bitcoin eliminates the need for central banks or executives who can print more money on a whim.

Today, Bitcoin is the largest cryptocurrency by market capitalization, held by individuals, institutions, and nation-states. But what is Bitcoin exactly, and how does it work? 

In this guide, Ledger Academy explains what Bitcoin is, its creation process, why it has value, and, most importantly, what it really means to own it.

What is Bitcoin and How Does It Work? 

As mentioned earlier, Bitcoin relies on a shared public ledger called a blockchain, which permanently records every transaction that has ever taken place on the network. Instead of existing on a single server owned by a bank, this ledger is copied and shared across tens of thousands of computers globally. Every participant holds the same version, meaning that no entity controls it exclusively.

Every new group of transactions is bundled into a block, and each block is linked chronologically using cryptography. This forms the blockchain, a continuous, tamper-resistant record extending back to the very first Bitcoin transaction in January 2009. The cryptographic linking ensures that if any single block is altered, all subsequent blocks in the chain break, causing the entire change to be instantly rejected by the network.

This mechanism is the basis of Bitcoin’s operations, effectively removing the need to rely on a specific individual or financial institution. Instead, the mathematical framework itself enforces the rules.

What Is Bitcoin Mining?

New BTC is typically created through a process known as mining. 

To explain, whenever you initiate a Bitcoin transaction, it is broadcast across the network. Network participants, known as miners, collect these transactions and organize them into a block. 

To validate and append this block to the blockchain, miners must compete to solve a complex computational puzzle. The first miner to successfully solve the mathematical puzzle earns the right to add the next block to the chain and collect a block reward, which comprises a block subsidy (a set amount of newly created BTC) and transaction fees. This rewarding process is the only way new BTC is introduced into circulation.

Additionally, the block subsidy is subject to a halving event, which is programmed to cut the amount in half approximately every four years (specifically, every 210,000 blocks). The halving gradually slows down the rate at which new Bitcoin enters circulation. As of the most recent Bitcoin halving in April 2024, that reward sits at 3.125 BTC per block.

More importantly, unlike fiat money, the amount of Bitcoins that can enter into circulation is capped at 21 million coins. Once all coins are mined, approximately by 2140, no new coins will be issued, meaning that the block subsidy component of block rewards will no longer be available. Instead, miners’ compensation will come entirely from the transaction fees paid by users.

Energy Consumption and Proof-of-Work

Proof-of-work (PoW) is the consensus mechanism that Bitcoin uses to add new transactions to the blockchain and maintain the network’s integrity. By naturally allowing blocks to have probabilistic finality, it plays a significant role in preventing the double-spending problem, where a user tries to spend the same digital coin twice.

PoW is technically designed to make creating a new block computationally expensive, but verifying its validity cheap. To cheat with an invalid block, an attacker would have to redo all that computational work on every block faster than the rest of the network combined. In practice, that’s effectively impossible. That being said, since the machines performing the “work” consume lots of energy, the network has sparked debates about its environmental footprint. However, in recent years, the mining sector has increasingly adopted renewable energy and utilized energy sources that would otherwise be wasted. For a more detailed explanation, you can explore the mechanics of how Bitcoin mining works.

Who Created Bitcoin?

In October 2008, the whitepaper: “Bitcoin: A Peer-to-Peer Electronic Cash System” was published under the pseudonym Satoshi Nakamoto. The following January, the first Bitcoin block, known as the Genesis Block, was mined.

The true identity of Satoshi Nakamoto remains one of the great mysteries of the digital era. It remains unclear whether it is a single person or a collective.  Around 2010, Satoshi withdrew from public communication, allowing the blockchain to continue evolving autonomously.

Bitcoin’s Scalability, Decentralization, and Upgrades

Bitcoin, like other blockchains, contends with the blockchain trilemma – the inherent challenge of achieving optimal levels of security, decentralization, and scalability simultaneously. The Bitcoin network specifically prioritizes security and decentralization, a trade-off that results in limited scalability.

This choice to prioritize decentralization is what gives Bitcoin its remarkable resilience against censorship, seizure, and manipulation – qualities that no traditional bank accounts or fiat currencies can match. This robustness stems from the absence of a single point of failure: there are no central servers to disable, no CEO to target, and no policy team to pressure. 

Simply put, the network continues to function as long as some nodes and miners remain active. Rather than being governed by a central authority, the network’s continuous operation is currently maintained by thousands of geographically dispersed participants.

Since scalability is sacrificed, the Bitcoin base layer currently processes about 7 transactions per second. This capacity is significantly lower than that of other major payment processors, such as Visa, which handles around 1,700 to 65,000 transactions per second. 

Bitcoin Improvement Proposals

Because Bitcoin lacks a central governing body, its development is driven by a diverse group, including its community, developers, miners, and other stakeholders. To implement changes to the protocol, these groups must propose, discuss, and agree upon them, a process formally managed through Bitcoin Improvement Proposals (BIPs).

BIPs frequently focus on enhancing Bitcoin’s core goals, which include security, privacy, and functionality. Among these, improving the network’s scalability is a key objective, and several important BIPs have been introduced to address related challenges. Some of these include:

• SegWit – Segregated Witness (SegWit) enhanced Bitcoin’s scalability by reducing transaction sizes. It achieved this by separating the signature data (or witness data) from the main transaction data. This alteration successfully raised the block capacity, potentially allowing for a block size of up to 4MB.
• The Taproot Upgrade – The Taproot upgrade further enhanced efficiency by reducing the data size of complex transactions. One of its primary mechanisms is Schnorr signature aggregation, which combines multiple digital signatures into a single, compact signature. This reduction in data size allows more transactions to be included within each block.

In summary, BIPs, while primarily focused on enhancements to the Bitcoin blockchain itself, have also been instrumental in establishing the necessary cryptographic and scripting foundation for layer 2 protocols. A key example is SegWit, which, by resolving transaction malleability and increasing block capacity through the separation of offchain transaction data, made the Lightning Network possible.

The Lightning Network is the most prominent layer-2 solution for Bitcoin. Built on top of the main network, it is designed to address Bitcoin’s throughput limitations without compromising its fundamental decentralization. It achieves near-instant, virtually free transactions by committing only the final, settled balances to the main blockchain.

Why Does Bitcoin Have Value?

Bitcoin functions as a digital store of value and a medium of exchange, with unique properties that distinguish it from fiat currencies. That being said, its value can be attributed to several factors, including:

1. Scarcity and Supply Control

Bitcoin has a hard cap of 21 million coins, a limit hardcoded into its underlying source code. This stands in stark contrast to conventional fiat money, where central banks can increase the money supply at will. When governments print more currency, it typically weakens the purchasing power of each existing unit through inflation.

As demand for Bitcoin grows while the supply remains fixed, scarcity becomes a primary value proposition. This is why Bitcoin is often called “digital gold.” Like physical gold, it is scarce, difficult to produce (mine), and under no government’s control. However, unlike gold, Bitcoin is highly portable and can be sent across the world in minutes.

The rate at which new Bitcoin enters circulation decreases by half approximately every four years through a mechanism called the “halving.” These events serve as a strict supply control. While past performance does not guarantee future results, halving events have historically preceded significant market changes.

At the time of writing, roughly 19.99 million BTC out of the maximum supply have already been mined. However, the actual amount circulating is significantly less, owing to permanently lost Bitcoin, which is estimated to be around 3 to 4 million. These losses often result from forgotten private keys, lost storage devices, or intentional coin burning. 

This scarcity typically increases the value of the remaining Bitcoin, a concept Satoshi Nakamoto noted as: “Lost coins only make everyone else’s coins worth slightly more. Think of it as a donation to everyone.”

2. Network Effect and Demand

The network effect is a key driver of Bitcoin’s value. This principle states that as more individuals, businesses, and institutions adopt and use Bitcoin, the network becomes more secure and valuable. Increased utility and a larger market capitalization create a cycle that continues to drive Bitcoin’s market presence upward.

3. Divisibility

One BTC is divisible into 100 million smaller units called satoshis (sats). This divisibility ensures that Bitcoin remains practical for any transaction size, from tiny microtransactions to large-scale institutional exchanges.

This feature ensures that Bitcoin remains accessible to everyone, regardless of its market price. For example, even if 1 BTC were valued at $1 million, a single satoshi would be worth approximately $0.01, allowing for precise pricing and everyday use.

What Are the Risks of Owning Bitcoin?

While Bitcoin is fundamentally transforming and disrupting the traditional financial landscape, offering a decentralized alternative to currencies and conventional banking systems, owning it comes with certain risks. These risks include:

• Market volatility – Bitcoin, much like any other cryptocurrency, is inherently volatile in nature. Its value can rise or fall dramatically in short periods. This price fluctuation is often driven by factors such as regulatory news, market sentiments, macroeconomic trends, or even protocol upgrades. 
• Transaction irreversibility – Bitcoin transactions, unlike credit card payments, cannot be charged back or reversed. Once sent, the transaction becomes immutable and is permanently recorded on the blockchain, even if it is sent to an incorrect address. This necessitates that the user takes full responsibility for ensuring accuracy.
• Security risks and hacking – While the underlying protocol itself is highly secure, the exchanges, crypto wallets, and other methods used to store and trade Bitcoin are vulnerable to cyberattacks, hacking, and theft. The blockchain’s immutable nature means that if your Bitcoin is stolen due to a compromised private key or an exchange hack, the funds are virtually impossible to recover.
• Scalability and transaction fees – Increased adoption and utility of Bitcoin can lead to network congestion and slower transaction processing. When demand is high, users compete for limited block space, which can significantly raise transaction fees as they try to prioritize their transactions. This makes using the main blockchain for small, daily payments uneconomical. However, layer 2 solutions, such as the Lightning Network, address this issue by facilitating transactions offchain.

How Do You Actually Own Bitcoin? Digital Ownership Explained

Most people don’t realize this when they first acquire Bitcoin: purchasing it and truly owning it are two separate things.

When you purchase Bitcoin via an exchange and leave it there, you don’t actually hold the Bitcoin itself. Instead, you hold a record in the exchange’s database indicating that the exchange owes you Bitcoin. The exchange is the one that controls the actual Bitcoin, or more accurately, the private keys that grant access to your Bitcoin, which lives in the blockchain.

What Is a Private Key?

Every Bitcoin address on the blockchain has a corresponding private key, a unique cryptographic string that proves your right to spend the Bitcoin at that address. Think of it as the master password to your funds. And whoever controls the private key controls the Bitcoin.

When your Bitcoin sits on an exchange, the exchange is actually holding your private keys. With that said, if the exchange is hacked, goes bankrupt, freezes withdrawals, or simply vanishes, your Bitcoin goes with it. 

Digital Ownership: True Bitcoin Ownership

One of the most common mantras alluding to true ownership of Bitcoin, or any other cryptocurrency, is: “Not your keys, not your coins.” This means that to actually own your digital asset, you must hold your private keys, putting yourself in complete control of your Bitcoin instead of a third party.

The best practice for achieving true digital ownership, or self-custody, is using a signer (or hardware wallet). This physical device keeps your private keys offline, isolating them from potential online attack vectors. When executing a transaction, you simply approve or sign it directly on the signer, ensuring your keys never interact with an internet-connected device.

Think of it as keeping gold bars in your own safe versus entrusting them to a bank and hoping for its continued solvency. To truly own your Bitcoin, acquiring a secure Bitcoin wallet is essential. Furthermore, you can compare the best Bitcoin wallets to identify the most suitable option for their specific requirements.

How to Buy and Store Bitcoin Safely

Step 1: Set Up Your Ledger Wallet

Before purchasing even a single satoshi, you must first set up a wallet as follows:

1. Purchase a Ledger signer if you do not already own one.
2. Install Ledger Wallet^TM on your computer or mobile device using the official Ledger website. Ensure the app is updated to the latest version.
3. Initialize your device by setting a secure PIN and carefully writing down your 24-word secret recovery phrase (SRP).
4. Install the Bitcoin app on your Ledger signer via Ledger Wallet^TM to create your Bitcoin wallet.

Step 2: Buy Bitcoin Safely Using Ledger Wallet^TM

Here are the steps to buy Bitcoin directly into your Ledger:

1. Access the Buy/Sell Section: Open the Ledger Wallet^TM app and navigate to the “Buy/Sell” feature.
2. Select Asset and Service Provider: Choose Bitcoin (BTC) and select one of the on-ramp service providers, such as MoonPay, Coinbase Pay, and Topper. Consider factors such as geographic eligibility, fees, and payment options (credit/debit card, Apple Pay, Google Pay, and direct transfer).
3. Enter Transaction Details: Specify the amount in your local fiat currency (such as USD and EUR), and Ledger Wallet^TM will estimate the amount of BTC you will receive.
4. Confirm on Device: Carefully verify the transaction details and destination address on your Ledger signer’s secure screen. This mandatory step prevents malicious software from altering the recipient address.
5. Finalize Payment: Complete the purchase using your preferred method (e.g., bank transfer or credit/debit card). Once your Ledger signer approves the transaction, click the “Buy Now” or “Confirm” button on Ledger Wallet^TM to process the payment.

Step 3: Store Your Bitcoin Safely

Although the purchased BTC still lives on the Bitcoin blockchain, the associated private keys required to access it are securely stored in your Ledger signer, away from the internet. This means you retain complete control and ownership of your private keys, and thus your BTC. 

You’ll receive a sequence of 12–24 words when setting up your Bitcoin wallet. This phrase is essential for regaining access to your assets if your Ledger signer is lost or damaged. More importantly, never share your SRP or PIN, and never store it digitally, including taking a picture. Losing this phrase might result in the permanent loss of your Bitcoin.

In short, by using a Ledger signer and Ledger Wallet^TM, you achieve non-custodial ownership. This means that you alone control your Bitcoin, rather than an exchange or bank.

The Broader Significance of Bitcoin Ownership

Bitcoin constitutes the first working proof that money can exist as a scarce, decentralized, and borderless asset without reliance on a central authority. Furthermore, when appropriately managed, it provides genuine self-sovereignty.

While grasping the underlying concept might require time, securing ownership only takes the right tools. The fundamental takeaway is straightforward: the security of one’s Bitcoin rests entirely with the person holding the keys. If that’s not you, then you merely possess a promise or claim of Bitcoin, and not the asset itself.

To actively participate in the ecosystem, one must acquire a secure Bitcoin wallet and take complete control over their private keys.

Frequently Asked Questions (FAQs)

1. Is Bitcoin Legal?

In most countries, yes. Bitcoin is legal to buy, hold, and use in the majority of jurisdictions globally. However, regulations vary significantly by country, and some nations have imposed restrictions or outright banned it.

2. Is Bitcoin Anonymous?

Not exactly.  Bitcoin is pseudonymous. Transactions are recorded publicly on the blockchain, linked to wallet addresses rather than names. But those addresses can sometimes be traced back to identities through exchange records, IP data, or other onchain analysis.

3. Can Bitcoin Be Hacked?

The core Bitcoin network is widely regarded as nearly impossible to compromise and has never been successfully hacked. Altering the blockchain would require an attacker to control over 50% of the network’s computational power, a computationally expensive feat.

When breaches do occur, they typically target centralized entities like exchanges, custodians, and software wallets that manage Bitcoin holdings on behalf of users, rather than the Bitcoin network itself.

4. What Happens When I Lose My Private Keys?

Losing your private keys means permanent loss of access to your Bitcoin unless a backup exists. Without the private key and no way of recovering access, there’s no way of retrieving your funds.

5. What Is The Smallest Unit of Bitcoin?

One satoshi, coined after the pseudonymous Bitcoin creator(s), Satoshi Nakamoto, is equivalent to 0.00000001 BTC. In other words, 1 BTC equals 100 million satoshis. It’s the smallest divisible unit.