# Supercomputer

> Thousands of computers wired together to work on one huge calculation at once.

- Level: Intermediate
- Topics: Hardware
- URL: https://tidbit.legios.com.ar/supercomputer/
- In Spanish: [Supercomputadora](https://tidbit.legios.com.ar/es/supercomputer/)

A **supercomputer** is not one giant processor. It is thousands of ordinary-looking servers, called nodes, packed into rows of racks and connected by an extremely fast network so they can behave like a single machine. Each node has its own CPUs, and today most of the computing power comes from GPUs. The total can reach more than a quintillion calculations per second, the level known as **exascale**.

The trick is splitting one big problem into many small pieces that run at the same time, then combining the results. That works well for simulations: weather and climate forecasts, how a new drug molecule folds, how air flows over a wing, how a nuclear weapon ages without testing it. This field is called **high-performance computing**, or HPC. The fast network matters as much as the chips, because the pieces constantly need to exchange data with their neighbors.

Twice a year, the TOP500 list ranks the fastest public supercomputers in the world; the top spots usually belong to national laboratories in the United States, Europe, Japan and China. The line with AI has blurred: the clusters that big companies build to train large language models use the same ingredients (thousands of GPUs, fast networks, heavy cooling) and are, in practice, supercomputers. They also consume a lot of power, often tens of megawatts, roughly what a small town uses.

## An analogy

Building a cathedral from Lego with ten thousand friends. Each person assembles one small section at the same time, and a very good system of runners carries pieces and instructions between tables. Nobody is fast alone; the speed comes from how many work at once and how well they coordinate.

## Keep in mind

- Thousands of nodes with CPUs and GPUs, connected by a very fast network.
- Splits one big problem into pieces that run in parallel.
- Used for climate, physics, medicine and engineering simulations, and now AI training.
- The TOP500 list ranks the fastest ones twice a year.

## Go deeper

- [Supercomputer on Wikipedia](https://en.wikipedia.org/wiki/Supercomputer)
- [TOP500 list](https://www.top500.org/)

## Related terms

- [CPU](https://tidbit.legios.com.ar/cpu/): The chip that runs your programs, one instruction after another, very fast.
- [Server](https://tidbit.legios.com.ar/server/): A computer whose job is to answer requests from other computers, all day, every day.
- [GPU](https://tidbit.legios.com.ar/gpu/): The chip that does thousands of simple calculations at once.
- [Forecasting](https://tidbit.legios.com.ar/forecasting/): Using past data to estimate future numbers, with an honest range around the guess.
- [Chip](https://tidbit.legios.com.ar/semiconductor-chip/): A sliver of silicon carrying billions of tiny switches that compute and remember.
- [Artificial intelligence](https://tidbit.legios.com.ar/artificial-intelligence/): Getting computers to do things that, until recently, only people could do.
- [Training and inference](https://tidbit.legios.com.ar/training-and-inference/): Training builds the model once; inference is using it, millions of times a day.