Books, courses, the maths you need, the software people use, and the questions beginners keep asking. Each claim on this page says where it came from.
This page exists because the same questions come up wherever people meet quantum computing: how do I start, what do I read, how much maths, which software, do I need a PhD, is it real. We looked at what people ask in public, and built the page around it. Where the answer is in a lesson here, it links there. Where we have no sourced answer, it says so.
Where the questions came from, honestly. Hacker News “Ask HN” threads (50 of them, by points), a list of eight questions students ask published by the company QuEra, and the help forum of QuTiP, the simulation tool the Workbench teaches. We tried to read r/QuantumComputing and Quantum Computing Stack Exchange and our tools were not allowed to open either, so this is not a sample of Reddit. The subreddit’s own description says it keeps a weekly thread for career, education, textbook and basic questions; the four headings of this page are the same four.
From the Hacker News threads, with the points each earned, and from the two other sources. The right-hand column is a link, or a plain “not covered”.
| The question, as asked | Where it was asked | Where we answer it |
|---|---|---|
| What has quantum computing achieved so far? | Ask HN, 164 points, 122 comments | Did the advantage last?, The Race, the timeline |
| Where do I start learning? Which resources? | Ask HN, 185 points; many more at 1 to 26 | Start here, What is a qubit?, and the sections below |
| What would quantum do to Bitcoin and encryption? | Ask HN, several threads from 2 to 11 points | Can quantum break Bitcoin?, post-quantum tools |
| Does a quantum computer test every solution at once? | An HN post titled as a correction | The Reality Check card |
| Is it hype? Will it scale? How long? | Ask HN, several threads; QuEra’s list | The Ledger: dated claims, scored when they fall due |
| How do AI and quantum computing meet? | QuEra’s list | Will quantum make AI more powerful?, How does AI fix quantum errors? |
| Why neutral atoms, and how do they differ from ions and superconducting qubits? | QuEra’s list | Quantum computing companies compared |
| What maths do I need? | Ask HN, QuEra’s list | Below |
| Which book, which course? | Ask HN, the largest group | Below |
| Which software should I learn? | Ask HN (“Q# … what’s the future?”, “does studying languages make sense yet?”) | Below; Qiskit and Cirq side by side in lesson 40 and 41 |
| Do I need a PhD? Where are the jobs? | QuEra’s list; Ask HN (PhD programmes) | Below |
| How do I simulate a superconducting qubit? (units, noise, pulses) | QuTiP’s help forum | The Workbench, with a “people keep asking” box in four of its lessons |
| How do quantum computing companies make money? | Ask HN, 44 points, asked twice | Not covered yet |
It depends on how deep you go, and the lessons here are written so that you can stop at any rung. IBM’s Basics of quantum information course says it suits people in computer science, physics, engineering and mathematics, and recommends familiarity with basic linear algebra, complex numbers and elementary notions about sets and functions (its course page). The ladder below is our own, and each rung names the lesson that teaches what it asks.
If a lesson uses a piece of maths you do not have, the glossary and the Lexicon underlines on the page give a one-line definition and the lesson that teaches it.
| What | What it is | Where we got that |
|---|---|---|
| John Preskill, lecture notes for Physics/CS 219, Caltech | The lecture notes for his course on quantum computation, free to read online. His course page calls them the primary reference for most lectures and lists Nielsen and Chuang, Kitaev, Shen and Vyalyi, Aaronson’s book, Watrous and Wilde as supplementary. | preskill.caltech.edu/ph219. His course pages now live at this address. |
| Michael Nielsen and Isaac Chuang, Quantum Computation and Quantum Information, 10th Anniversary Edition | A textbook, Cambridge University Press, ISBN 9781107002173. Some lessons here cite it by chapter. | Cambridge University Press listing (it gives the date as January 2011; some resellers say December 2010). |
| Scott Aaronson, Quantum Computing since Democritus | Cambridge University Press, 2013. It opens with ancient atomism and moves through set theory, computability, complexity, quantum computing, cryptography and interpretations of quantum mechanics. A Choice Outstanding Academic Title of 2013. | Cambridge University Press listing |
| IBM Quantum Learning, Understanding quantum information and computation (John Watrous) | A series of four courses: Basics of quantum information, Fundamentals of quantum algorithms, General formulation of quantum information, and Foundations of quantum error correction. The first uses Qiskit, ends with an exam and a badge, and is described as advanced-undergraduate to introductory-graduate level. Check IBM’s catalogue for current terms. | The course page |
| This site | What is a qubit? (20 minutes), the pillar pages at three depths, The Machinery (41 topics of mathematics, 18 of them on simulating real circuits and writing them in Qiskit and Cirq) and the Workbench. | Written here; every number is re-derived by a script when the site is built. |
We list four things we could check. We did not list a book or course we could not confirm, and we make no claim about which is best.
There is a family of free tools and they do different jobs. The table says who built each one and what its own pages call it. We found no public source that says which a given company or laboratory uses internally, so this page does not say, and it does not rank them.
| Tool | Built by | What its own documentation says it is |
|---|---|---|
| Qiskit | IBM | An open-source quantum software development kit. Version 2.0 was released on 31 March 2025 and removed Qiskit’s own pulse module, pointing former users to Qiskit Dynamics. |
| Cirq | Google Quantum AI | An open-source Python framework for creating, editing and running circuits for noisy intermediate-scale quantum hardware and simulators; Apache-2.0; first announced as a public alpha in 2018. |
| PennyLane | Xanadu | An open-source Python library for quantum machine learning, automatic differentiation and optimisation of hybrid quantum-classical computations, with plugins for several hardware and simulator back ends. |
| CUDA-Q | NVIDIA | A programming model and toolchain for CPUs, GPUs and quantum processors working together, in C++ and Python. |
| Amazon Braket | Amazon Web Services | A fully managed service giving access to quantum hardware and simulators through one development environment, billed by use. The list of hardware providers has changed since its 2019 launch, so check its page. |
| Microsoft QDK | Microsoft | An open-source developer toolkit with VS Code integration, local simulators and resource estimation; it supports Q#, QIR, OpenQASM, Qiskit, Cirq and Python. |
| QuTiP and scqubits | Community projects (QuTiP); Groszkowski and Koch (scqubits) | The physics of the chip instead of the circuit: how a superconducting qubit’s state changes in time (QuTiP) and what its energy levels are (scqubits). This is what the Workbench teaches. |
A way to choose, from what the descriptions say and nothing more. To write circuits and run them on simulators or hardware: Qiskit, Cirq, Braket or the QDK. For gradients and machine-learning work on hybrid circuits: PennyLane. For GPU-accelerated simulation and hybrid programs: CUDA-Q. For the physics under a superconducting qubit, with Hamiltonians, noise and pulses: QuTiP and scqubits. A circuit-level lesson for Qiskit and Cirq is on this site: topic 40 writes the same circuits in both, and topic 41 compiles them for a chip and adds noise. For the others in that group, see what is not covered.
One company, QuEra, published a list of eight questions students ask it. On the PhD question it says: “The short answer: not necessarily.” It adds that deep academic specialisation helps for some paths while engineering and computational skills suit others, across hardware, software, applications and product roles, and it names chemistry, pharma, finance, logistics and materials as the industries it expects early value in. It does not answer the other questions it lists (which skills to prioritise, what is overhyped, how to get undergraduate research).
What that is and is not. It is one company’s view of its own field. It is not hiring data, it says nothing about salaries or openings, and we have no survey to put beside it. If you want to test whether the work suits you before you decide anything, the twenty-minute lesson and the first five topics of the Workbench need no degree and no installation. Source: QuEra, “What the next generation wants to know about quantum computing”.
Compiled 25 October 2026; the Qiskit and Cirq lessons were added the same day. Reviewed by: not yet. Corrections: tell us.