The most important computing revolution in the last 60 years has begun with the integration of classical computing, quantum computing, and artificial intelligence. Although quantum computing is still a young discipline, specialized in the construction of hardware and software using the quantum properties of nature, it is called to play a relevant role in this computing revolution because of its ability to solve, in various business areas, problems of such complexity that classical computing cannot address.

In this paper, framed in this technological context, the authors present a pragmatic study of the main areas of quantum computing, focusing in particular on software and the need for the existence of a true Quantum Software Engineering (QSE) to produce quantum software with sufficient quality and productivity, which is the fundamental axis for the diffusion of quantum computing.

In order to achieve the objectives of the paper, the exposition of the content is carried out through this structure:

1.     Introduction

2.     Quantum Computing History

3.     Basic Quantum Concepts

4.     Quantum Hardware

5.     Quantum Software

6.     Quantum Software Challenges

7.     Conclusions

After a brief overview of the different industrial ‘revolutions’, the authors conclude the introduction by suggesting that the next revolution will come from nanotechnology, biotechnology, genomics and quantum computing, based on the exploitation of the properties of quantum mechanics.

In the remainder of the article, the authors present the history of quantum computing (Section 2) and the main concepts of quantum mechanics and quantum computation on which quantum computing is based (Section 3). In Section 4, they summarize the main quantum technologies used to build qubits and the different types of quantum computers.