Introduction to Quantum Computing and OpenQASM

Welcome to the fascinating world of quantum computing! Quantum computers are not just faster versions of classical computers; they operate on fundamentally different principles, harnessing the peculiar properties of quantum mechanics to solve certain problems more efficiently.

What is OpenQASM?

Open Quantum Assembly Language (OpenQASM) is an intermediate representation language for quantum circuits. It allows for the description and manipulation of quantum programs, bridging the gap between high-level quantum algorithms and the low-level instructions that quantum processors execute. OpenQASM is particularly well-suited for designing experiments that test the capabilities of quantum computers with shallow (small depth) circuits.

Developed by researchers at IBM, OpenQASM was first introduced in a paper published on July 13, 2017, by Andrew W. Cross, Lev S. Bishop, John A. Smolin, and Jay M. Gambetta.1

Why Learn OpenQASM?

Understanding OpenQASM is beneficial for several reasons:

  • Intermediary Representation: It provides a framework for converting high-level quantum algorithms, expressed in languages like Qiskit or PyQuil, into a format that can be executed on actual quantum hardware or quantum simulators.
  • Accessibility: OpenQASM is relatively straightforward and designed to be easy to understand for those familiar with classical assembly languages or basic programming concepts.
  • Quantum Experimentation: It helps users define quantum circuits expressly for experimentation, which is crucial in current quantum research where debugging and testing new quantum algorithms is a frequent activity.

Running OpenQASM

You can experience OpenQASM in multiple environments:

  • photonq.org2: Our dedicated platform for learners like you to explore quantum computing concepts including OpenQASM.
  • IBM Quantum Experience3: IBM offers a cloud-based platform where you can use a graphical interface called the Composer to build quantum circuits using OpenQASM. You can also connect to their quantum processors to execute your quantum programs.
  • Qiskit4: This open-source framework for quantum computing allows you to create quantum circuits, compile them into OpenQASM, and run them either on simulators or actual quantum hardware. The ability to convert between Qiskit and OpenQASM makes it flexible to switch between high-level abstraction and low-level execution.

Let's Get Started with OpenQASM!

Now that you have a foundational understanding of OpenQASM and its relevance to quantum computing, it's time to dive deeper. In the next chapters, we'll explore the syntax and structure of OpenQASM, create simple quantum circuits, and run them on simulators and quantum computers. Let the quantum journey begin!


  1. Cross, A. W., Bishop, L. S., Smolin, J. A., & Gambetta, J. M. (2017). Open Quantum Assembly Language.

  2. Photonq Experiment

  3. IBM Quantum Experience

  4. Qiskit GitHub

Learn about OpenQASM

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