Supercomputing is a technology that has enabled revolutionary breakthroughs. The development of new, even more powerful computers will transform almost every industrial sector, from the development of new pharmaceuticals and connected health systems to the creation of more efficient manufacturing processes and more sustainable technologies.

Supercomputers enable scientific achievements that the human intellect alone would be unable to achieve. It is also one of the most advanced technologies in recent years. In 1985, high-performance computers processed 1.9 gigaflops; almost two billion operations per second. Today, commercial video game consoles are a thousand times more powerful. At the same time, there are more than 500 supercomputers that exceed a petaflop, i.e. they are more than a million times more powerful than their ancestors of the 1980s.

But what exactly is a supercomputer, and how is it different from a desktop computer? A traditional computer usually has a single 'brain': the processor. This electronic device allows it to carry out mathematical operations and thus process information very quickly. In a supercomputer, thousands of processors are connected together, working as a team to process operations all together. Thanks to parallel operation, supercomputers can process large amounts of data extremely fast, and are ideal devices for carrying out complex operations such as monitoring a storm in real time, carrying out simulations that are essential for scientific development, or even processing the special effects and 3D animations of the latest blockbuster films.

In addition to impressive computing and data processing capabilities, supercomputers are also capable of storing huge amounts of data, offering digital storage services such as the famous 'clouds' that keep all our emails, photos and documents online. One example is the 'Summit' supercomputer, built by IBM for the US Department of Energy, which can store 250 petabytes of information, the equivalent of almost 30 million DVD discs. Summit combines more than 9000 processors, a 'brain' capable of processing at speeds of 150 petaflops.

Finally, it is worth highlighting another key property of supercomputers: connectivity. For, once again, there is strength in numbers. Thanks to high-speed network connections, several supercomputers can be interconnected to create 'clusters' and networks, coordinated structures that maximise computing power.

In this regard, the Spanish Ministry of Education and Science promoted the creation of the Spanish Supercomputing Network (RES) in 2007. The RES, led by the Barcelona Supercomputing Center, connects 16 supercomputers in 11 autonomous communities. Together, thanks to the high-performance connections provided by RedIRIS, they reach a processing speed of 13 petaflops.

Supercomputers are a tremendously useful tool for scientific and technological development. The Barcelona Supercomputing Center itself explains how these machines help us to simulate reality in order to understand it better, opening up a world of unusual possibilities. Some of the applications of supercomputing make it possible to predict the aerodynamics of an aircraft and detect its problems without the need for a wind tunnel, to understand the functioning and possible side effects of a drug before testing it on animal models and patients, and to predict the effects of climate change, as well as the emission reduction measures planned by companies and governments. The director of the Barcelona Supercomputing Center, Mateo Valero, believes that these technologies are essential for the advancement of society. Cooperation between computers and clusters also opens the door to collaborations between different research groups. For this reason, the RES is working to broaden the culture surrounding supercomputing in Spain, favouring multidisciplinary work and promoting the development of new machines and infrastructures.

During the COVID-19 pandemic, supercomputing has played a key role in developing models to better understand the structure of the coronavirus, design drugs to combat the effects of the disease and unravel the mechanisms of transmission. In this regard, the Partnership for Advanced Computing in Europe (PRACE) launched a call in spring 2020 to fund and accelerate computational research to help mitigate the effect of the pandemic. Thanks to this call, several groups of scientists were given priority access to supercomputers in France, Germany, Italy, Switzerland and Spain. A year later, PRACE announced the most successful results, including several detailed studies of the structure of the spicule protein, which is central to the coronavirus infection process; models that scanned databases of drugs and chemical compounds to identify new antiviral drugs; and detailed fluid mechanics simulations that provided a better understanding of aerosol dynamics and how the disease spreads. A Sorbonne researcher involved in these PRACE projects highlights in an interview the importance of supercomputing, which has enabled some of the most complex simulations to date, fundamental to finding answers and results in record time.

Supercomputing can help us solve extremely complex problems; it is a central technology for scientific progress and innovation. The European Commission will increase its investment in this field over the coming years, both as part of its 'Horizon Europe' research programme and as part of the EU's overall budget. Supercomputing is now a priority, key to the bloc's economic recovery.