What is quantum computing?

Quantum computing is a rapidly evolving field that harnesses the principles of quantum mechanics to process information in fundamentally new ways.

Unlike classical computers, which rely on bits that exist as either 0 or 1, quantum computers use qubits, which can exist in multiple states simultaneously via a process called superposition. This enables them to perform complex calculations exponentially faster than traditional computers, opening new frontiers in industries like drug discovery, cryptography, and materials science.

Quantum computing could soon process data at speeds that even supercomputers cannot.

This is deep tech, backed with billions in funding. In April 2026, McKinsey & Company published research that found quantum technology startups raised $12.6 billion in 2025, a 6.3-fold increase on 2024.

Latest Videos From

Watch full video here:

Governments are also investing heavily in quantum computing. In March, the UK government pledged up to £2 billion ($2.71 billion) as part of a larger procurement plan for companies in the quantum sector. The US government has also announced $65 million in funding for ten quantum computing projects.

How do quantum computers work?

The foundation of quantum computing was laid in the early 20th century with the advent of quantum mechanics. Richard Feynman, a pioneering physicist, introduced the idea of using quantum systems to simulate physical processes in the 1980s. The first experimental quantum computers emerged in the late 1990s, and since then, companies like Google, IBM, and Microsoft have made significant strides in building scalable quantum hardware.

Computers as we know them, from bulky desktop machines to the iPhone X, all work in much the same way, regardless of their power or size. They perform operations by storing information as conventional bits, taking the form of either 0 or 1.

While classical computers work by encoding information into bits, quantum computers run using aptly-named quantum bits or qubits. But there's a big difference between the two. A bit can be encoded as either 1 or 0, but qubits can take the form of 1, 0, or what is termed as a 'quantum superposition of 1 and 0'; the qubit exists in both states simultaneously.

Two bits, when stitched together, can exist as 00, 01, 10 or 11; and only one of these states at any one time. A quantum computer with two qubits, however, can be all four states – 00, 01, 10 and 11 – simultaneously.

When multiple qubits work in tandem to process calculations, the combination of states that can exist at once ramps up exponentially. A machine with three qubits, for instance, can exist in eight states, four in 16 states, and a 32-qubit strength machine can exist in a quantum superposition of nearly 4.3 billion simultaneous states.

These principles are hard to bend your mind around because they are fundamentally confusing. Even Nobel Prize-winning physicist Richard Feynman famously remarked: "I think I can safely say that nobody understands quantum mechanics".

Quantum computing relies on three core principles:

1. Superposition: Qubits can exist in multiple states simultaneously, vastly increasing computational power.
2. Entanglement: Qubits can be interconnected so that the state of one qubit is dependent on another, allowing for faster and more complex calculations.
3. Quantum gates: These operations manipulate qubits to perform computations that would be infeasible for classical computers.

IBM's Qiskit – one of the most advanced quantum computing frameworks – enables developers to design and run quantum algorithms, pushing the boundaries of computational science. “Advances across our hardware and Qiskit are enabling our users to build new algorithms in which advanced quantum and classical supercomputing resources can be knit together to combine their respective strengths,” commented Jay Gambetta, vice president of IBM Quantum.

Applications of quantum computing

Quantum computing is set to revolutionize industries by solving complex problems that are beyond the reach of classical computers. From accelerating drug discovery to optimizing financial models and enhancing cybersecurity, quantum technology is unlocking new possibilities. One promising intersection is with AI, where quantum computing is poised to enhance data processing and improve AI capabilities.

“AI and quantum computing connect in two ways,” Stefan Leichenauer, VP of engineering, SandboxAQ explains to ITPro. “First, AI is needed to enable quantum. A quantum computer is a special-purpose device that is only useful for certain tasks, namely those tasks which show a quantum advantage. So, a quantum computer is used as part of a larger workflow, and that larger workflow is an AI workflow – or is at least managed by an AI. AI is also necessary to calibrate and operate the quantum hardware efficiently.

Leichenauer adds that quantum computing can act as a “data generator for AI,” with quantum computers capable of producing new data on properties such as atomic states. These can in turn be paired with AI for applications such as drug and material discovery, as well as sustainable chemicals and energy research.

“That data can enable quantitative AI models, such as large quantitative models (LQMs), to push boundaries in those subjects that wouldn’t be possible without the quantum computers,” he says.

Quantum computing has vast applications across multiple industries:

• Drug discovery and material science: simulating molecular interactions with unprecedented accuracy.
• Financial modeling and optimization: enhancing portfolio management and risk assessment.
• Cybersecurity: developing quantum-safe encryption techniques to counter quantum threats.

Major concerns also surround the ability of quantum computers to break current encryption standards, potentially compromising sensitive data. Cybercriminals are already engaging in “harvest now, decrypt later” attacks, collecting encrypted data to decode once quantum computing becomes viable.

To address this threat, businesses are adopting post-quantum cryptography (PQC), which is now top of mind for cybersecurity leaders. Current cryptographic algorithms generate keys that are hard to crack with classical computers, such as RSA algorithms which multiply two large primes to produce a 'modulus' key that is extremely hard to crack. Quantum computers make cracking primes trivial, however, so post-quantum cryptographic algorithms such as those based on lattices, which pair geometric vectors together. These problems lack the structure necessary for quantum computers to easily solve them.

Organizations such as the Quantum-Safe 360 Alliance have also risen up to provide organizations with guidance on the adoption of PQC.

Unlike conventional encryption, QKD relies on the fundamental laws of quantum mechanics, making it theoretically immune to hacking. Organizations worldwide are already investing in quantum-safe cryptographic standards, ensuring that as quantum computers progress, security measures evolve alongside them. The future of cybersecurity will likely depend on a hybrid approach that integrates both classical and quantum-resistant encryption methods.

The future of quantum computing

Looking ahead, quantum computing holds the potential to revolutionize processes across different sectors. From advancing AI to discovering new materials, solving climate challenges, and optimizing global logistics, quantum computing could unlock solutions to some of humanity’s most pressing problems. While the technology is still in its early stages, breakthroughs in scalability and error correction suggest that practical quantum computing could be within reach in the coming decades.

Quantum computing is on the brink of transforming industries, but widespread adoption will require overcoming significant technical hurdles. Companies like IBM, Google, and emerging players like Oxford Ionics are driving rapid advancements toward achieving quantum advantage.