Bitcoin is often described as the beginning of the cryptocurrency era. In reality, however, it was not the first attempt to create digital money. Bitcoin merely represents a turning point in a long series of experiments with digital money.

Many years before its creation, cryptographers, programmers, and people interested in how money works were already trying to figure out how financial transactions could be carried out over the internet. The goal was to avoid having to rely on a bank, the state, or another intermediary. The aim was clear: to create money suited to the digital world - money that would be fast, secure, difficult to counterfeit, and, if possible, resistant to censorship.

The toughest obstacle was the so-called double-spending problem. In a digital environment, any file can be copied easily. If someone could copy a digital coin and spend it multiple times, the entire system would lose credibility. Most early projects therefore managed to solve only part of the problem. Some brought privacy, others digital scarcity, and others still introduced a proof-of-work mechanism. Only much later were all of these ideas combined into one functional whole.

One of the first people to address this problem seriously was the American cryptographer David Chaum. As early as 1983, he warned that the computerization of payments would fundamentally change the way privacy and control over money function. In his work, he described what digital payments might look like if they were not fully traceable and were not dependent on a single institution. Thanks to these ideas, Chaum is now often referred to as one of the fathers of digital money, and his work became an important foundation for the later emergence of cryptocurrencies.

Why the idea of digital money emerged

All pre-Bitcoin projects shared one ambition: to create money suited to the digital world. It is important to realize that the financial system of that time worked very differently from the one we know today. Most payments were slow, often dependent on bank business hours, and transfers between countries could take several days.

Younger generations can usually imagine that way of functioning today only from films or older television series, where people commonly used cash, paper checks, or manual payment processing.

That is precisely why one of the main goals was to make payments faster, simpler, and more efficient, and to improve the flow of money in the economy. Traditional electronic payments did gradually appear, but they always required a central authority to maintain the ledger, confirm transfers, and decide what counted as a valid transaction.

This brought two major weaknesses. The first was dependence on an intermediary that could block a payment, shut down the system, or yield to political and regulatory pressure. The second weakness was the double-spending problem: a digital file can be copied easily, so it was necessary to prevent the same "digital coin" from being spent twice. That was precisely the technical knot on which most early projects failed.

DigiCash and eCash: privacy before decentralization

The DigiCash project ranks among the most important predecessors of cryptocurrencies. In his work on so-called "blind signatures," David Chaum proposed a mechanism that allowed a bank to validate digital money without seeing its specific form and without being able to track afterward who paid whom. In other words, the goal was to create electronic cash with strong privacy protection.

Building on this idea, Chaum and Moni Naor decided to put the theory into practice and founded DigiCash in 1990. Its main product was the eCash system, often described as the first truly functional form of digital money.

In practice, it worked in such a way that the user, using special software, "withdrew" digital coins - cryptographically signed tokens - from a bank account. These coins were cryptographically signed by the bank and could be sent to merchants over the internet. The merchant would then send the coins back to the bank for verification and to have the value credited to the merchant's account.

The eCash system was actually deployed in practice in 1993/94 as the first digital money. Some banks, such as Mark Twain Bank in the United States, allowed their clients to use the system, and there were even early online stores where eCash could be used for payment. In the context of that period, this was a very advanced solution - the internet was still in its infancy, and online payments practically did not exist.

In principle, eCash was elegant, but it remained centralized. The system addressed privacy well, but it did not remove the central point of trust: the bank and the infrastructure operator remained indispensable. That was ultimately its greatest weakness.

DigiCash failed to achieve sufficiently broad adoption - the technology was too far ahead of its time, the internet was not yet widespread, and banks were not willing to implement the system on a large scale.

In the end, DigiCash filed for bankruptcy in November 1998. Even so, its significance should not be underestimated. Through this project, Chaum laid one of the foundation stones of future cryptocurrencies: the idea of digital cash protected by cryptography that can function without complete transparency toward third parties.

e-gold: digital money backed by gold

A different path was taken by the e-gold project, launched in 1996 by the American physician and entrepreneur Douglas Jackson together with Barry Downey. The system operated under Gold & Silver Reserve Inc., which handled both operations and the management of gold reserves.

It was not a cryptocurrency in today's sense of the word, but it was a very important experiment in internet money.

The key difference from today's currencies was that accounts were denominated in gold. That means the user's balance was not kept in dollars but, for example, in grams of gold. Every unit in the system was backed by real physical gold stored in vaults.

The user therefore did not own a mere "promise" but a claim to a specific amount of gold.

In practice, e-gold worked very simply. The user created an account, deposited funds, which were converted into gold, and could then send value to other users over the internet. Transactions were fast, inexpensive, and worked globally regardless of national borders.

At a time when online payments were only just emerging, this was a very progressive solution.

It was precisely the combination of simplicity, speed, and backing by a real asset that made it popular. Unlike today's fiat currencies, meaning currencies issued by the state and not backed by any commodity, e-gold had a direct link to physical gold.

That is why it earned the trust of a large number of users and, at the peak of its expansion, processed transactions worth more than two billion dollars a year and was backed by approximately 3.8 tonnes of gold.

The problem with e-gold, however, was the same as with other early systems: absolute dependence on the operator. Accounts, transfers, and rules were all managed by a single company. Once the system became attractive for money laundering and other illegal activities, a regulatory intervention followed.

In 2007, the U.S. Department of Justice charged the company with money laundering and with operating an unlicensed money-transmitting business. In 2008, the company's management pleaded guilty and the project was gradually shut down.

Founder Douglas Jackson did not end up in prison, but he received a suspended sentence, a fine, and an obligation to cooperate with authorities. The court also stated that the company did in fact hold gold corresponding to the value of the accounts and that it was not fraud in the sense of embezzling funds.

As for users, their funds were not lost immediately. The liquidation and reimbursement process was complicated, however, and took a long time. The entire case thus showed that even a functional and popular digital currency can disappear if it is fully dependent on a single company and the legal environment of a particular country.

It is often argued that e-gold became so successful that it started to compete with the traditional financial system. These assumptions, however, cannot be confirmed unequivocally. What remains a fact is that the main reason for its shutdown was the violation of regulatory rules and insufficient control over illegal activities on the network.

Hashcash: when "work performed" was not yet money

Another important step forward did not come from the payments sector but from the fight against spam. Because sending emails requires almost no cost, spammers can very easily send enormous numbers of unsolicited messages and overwhelm both users and entire systems.

As early as 1992, computer scientists Cynthia Dwork and Moni Naor came up with the idea that sending a message should require a small amount of computational work. Adam Back later built on this idea, developing it into the Hashcash system in 1997 and describing it in detail in 2002.

The principle was simple: the sender of an email had to attach a digital "stamp" to the message, and creating that stamp required a brief amount of computational effort. The computer had to find a special value, a so-called nonce, which, after processing, produced a hash with certain properties - for example, one beginning with several zeros.

This process could only be carried out by trial and error, which meant spending time and energy.

The key element was the asymmetry of the effort involved. Creating this "stamp" took a few seconds, but verifying it was almost instantaneous. For an ordinary user sending a handful of emails a day, this posed no problem. For a spammer trying to send millions of messages, however, it would have meant enormous computational costs.

Hashcash was not a currency in itself. It did not solve ownership, transfers, or the ledger. What it did contribute was something essential: the principle of proof of work. It showed that even in the digital world, it is possible to create something that is not free to produce and yet is very easy to verify.

It was precisely this idea that the creator of Bitcoin, Satoshi Nakamoto, later adopted, referring directly to Hashcash in the Bitcoin white paper. Hashcash therefore did not solve digital money as such, but it supplied one of its key technical components.

b-money: the first sketch of a decentralized currency

In 1998, computer scientist Wei Dai published the concept of b-money, which already comes surprisingly close to later cryptocurrencies. He published his proposal in the Cypherpunks community, which focused on privacy protection and the use of cryptography in the digital world.

It was a proposal for an "anonymous, distributed electronic cash system" in which participants would act under pseudonyms and jointly maintain a record of who owned which funds. The goal was to create a system that would function without any central authority, such as a bank or the state.

Dai described two possible variants of operation. In the first version, every participant in the network would keep a copy of the ledger and verify the transactions of others. New money would be created on the basis of computational work, much like in Hashcash.

The second version was more practical and assumed that transactions would be verified only by a selected group of participants. These "verifiers" would have to provide a financial deposit as a guarantee of honest behavior, which can be viewed as a precursor to today's Proof of Stake principle.

Interestingly, b-money did not address only money itself but also the broader functioning of the system. The proposal also included a mechanism for concluding and enforcing digital contracts between participants without intervention by a third party - something we now know, for example, as smart contracts.

But b-money remained only a proposal. It did not offer a practical implementation that would work reliably in a real open environment, and some of its assumptions were difficult to realize from today's perspective. Even so, it was an exceptionally important concept that laid the theoretical foundations of modern cryptocurrencies.

Its importance is also shown by the fact that Satoshi Nakamoto included b-money among the sources in the Bitcoin white paper and contacted Wei Dai during Bitcoin's development. Bitcoin also adopted some of its key ideas, such as the creation of money through computational work and the principle that network participants verify transactions together.

An interesting detail is that, in honor of Wei Dai, the smallest unit of the Ethereum cryptocurrency is called "wei."

1 ether = 1,000,000,000,000,000,000 wei (10¹⁸)

Bit Gold: digital scarcity according to Nick Szabo

Nick Szabo was a cryptographer, programmer, and legal scholar who spent years studying the functioning of money, trust, and digital systems. He is one of the most important figures of the early cryptographic community and is also regarded as the originator of the idea of so-called smart contracts.

Nick Szabo pushed thinking about digital money even further. At the end of the 1990s, he introduced the concept of Bit Gold, which he later described in more detail around 2005. His goal was to create a digital asset that would work in a similar way to gold - that is, something scarce, difficult to counterfeit, and independent of a central authority.

The basic idea was simple: scarcity would not arise physically as it does with gold, but through computational work. Users would have to solve complex cryptographic puzzles, that is, perform proof of work, in order to create new units. Each such result would be given a timestamp and stored in a public registry.

A key element was also the linking of these results into a single continuing chain. Each new task built on the previous one, creating a chain of connected proofs of work. This principle is very similar to what we now know as the blockchain - an immutable record of history that is difficult to alter retroactively.

Bit Gold, however, was never launched in live operation. Its main weakness was that the proposal did not fully remove the need for trust in certain parts of the system, for example in timestamping or in the management of the ownership registry. At the same time, it lacked a mechanism that would automatically coordinate participants in an open network and adjust computational difficulty.

Even so, Szabo formulated several key ideas without which Bitcoin would be hard to imagine today: digital scarcity, linking money issuance to computational work, publicly verifiable ownership, and the very idea of digital "gold." That is why Bit Gold is often described as Bitcoin's closest predecessor.

An interesting detail is that the similarity between Bit Gold and Bitcoin led to frequent speculation that Nick Szabo might be the creator of Bitcoin known as Satoshi Nakamoto. Szabo has repeatedly denied those speculations.

RPOW and other intermediate steps

Hal Finney is also worth mentioning - a cryptographer, programmer, and one of the key figures of the Cypherpunks community. Finney had long been occupied with the idea of digital money, and in 2004 he introduced the Reusable Proofs of Work project, or RPOW.

This project was no longer just a theoretical proposal but real software. Finney tried to solve a fundamental problem of earlier systems such as Hashcash: how to turn a one-time proof of work into something that could be reused and passed from one person to another.

The operating principle was as follows. A user first created a proof of work, for example through Hashcash, and then sent it to the RPOW server. In exchange, the server issued a digital token that could then be transferred further between users. This became the first practical demonstration that computational work can serve as the basis for transferable digital value.

Security also played an important role. The system ran on specialized secure hardware that was meant to ensure that even the server operator could not forge tokens or spend them twice.

Even so, RPOW had a fundamental limitation. For proper operation, it still needed a central server that users had to trust. And that was precisely the problem that reappeared in other projects as well: once a system depends on a single point, it ceases to be truly decentralized.

Similarly, other centralized digital currencies, such as Liberty Reserve, founded in 2006, ran into the same barrier. They could facilitate fast internet transfers and sometimes also a high degree of anonymity, but centralization made them an easy target both for state intervention and for abuse within the illegal economy.

The Financial Action Task Force, an international organization focused on combating money laundering, and the U.S. Department of Justice later described Liberty Reserve as an example of a system that had become a tool for large-scale money laundering. This was further proof that the mere digitization of money is not enough; without decentralization and a trustworthy consensus mechanism, a system cannot endure in the long term.

What pre-Bitcoin projects actually solved

If we look at these attempts as a whole, it becomes clear that each of them solved only part of the puzzle. DigiCash showed how to protect privacy through cryptography. e-gold demonstrated that people want to send value over the internet outside the traditional banking model. Hashcash introduced proof of work. B-money proposed distributed records and pseudonymous participants.

Bit Gold formulated digital scarcity and the chaining of proofs of work. RPOW demonstrated that such tokens could also be transferred in software. Yet no one managed to combine privacy, scarcity, verifiability, an open network, and protection against double spending into a single system that also would not require a central administrator.

Conclusion

As we have seen, attempts to create a digital currency existed long before Bitcoin, but none of them was as comprehensive. That is exactly where Bitcoin's uniqueness lies. Bitcoin did not come out of nowhere, and it did not invent all of its building blocks from scratch.

Its strength lay in the fact that, for the first time, it meaningfully combined several earlier ideas into one functioning whole: a peer-to-peer network, a public transaction history, proof of work similar to Hashcash, the chaining of blocks in time order, and a consensus mechanism that solves double spending without a central mint or bank.

In short, transactions spread through the network, nodes verify them, miners assemble them into blocks, and proof of work ensures that the most trustworthy record is the one into which the most work has been invested. That is exactly what made Bitcoin a breakthrough compared with its predecessors.

And perhaps it is symbolically fitting that, to this day, no one knows with certainty who is actually hiding behind the name Satoshi Nakamoto. How Bitcoin was born and why its author remained anonymous will be discussed in the next part of our educational series, in the article What Is Bitcoin.