Three layers
The word began as a joke about the third thing a computer needs.
Hardware
The physical machine.
Software
The instructions it runs.
Wetware
The living tissue doing the thinking.
Hardware, software, wetware
| Layer | What it is | Example |
|---|---|---|
| Hardware | The physical machine | A chip, a disk |
| Software | The instructions it runs | An operating system |
| Wetware | The living tissue that does the thinking | A brain, or neurons on an electrode array |
In a brain the three are not separate. Cells are the machine, and their connections are also the memory and the program, and they change as they run. That is the main thing the word points at.
Where the word came from
Nobody has settled who said it first. The Jargon File says it probably comes from the novels of Rudy Rucker. Wikipedia lists early popular uses in Bruce Sterling's Schismatrix (1985) and Michael Swanwick's Vacuum Flowers (1987). Rucker's novel Wetware, the second book of his Ware series, came out in 1988 and made the term familiar.
The brain as wetware, in numbers
The figure everyone quotes is 86 billion neurons, from a 2009 study. It rests on a small sample, and a recent critique puts plausible estimates between 61 and 99 billion. The brain's energy budget is usually given as about 20 watts. We compare that with chips on brain vs GPU power.
Wetware computers are real now
Researchers now grow human neurons and connect them to electrodes. The Swiss company FinalSpark runs a remotely accessible platform that has tested over 1,000 brain organoids and recorded more than 18 terabytes of data. In Australia, Cortical Labs showed cultured neurons improving at the game Pong, then announced a commercial unit called the CL1 in March 2025. The field goes by the name organoid intelligence.
None of this competes with silicon yet. Organoids are fragile, live for months at best, and are hard to program. FinalSpark's own paper reports lifetimes of up to about 100 days in the best cases.
Questions
What is wetware in simple terms?
Wetware is the living part of a computing system: a brain treated as a computer, or lab-grown neurons connected to electronics.
Is wetware the same as AI?
No. Most AI runs on silicon chips and only borrows the idea of neurons. Wetware uses actual living cells.
Are wetware computers conscious?
Nobody has shown that. The main research programme on organoid intelligence states that it does not aim to recreate human consciousness, and consciousness in these systems remains an open ethical question.
Sources
- Wetware (brain), Wikipedia
- Wetware (novel), Wikipedia
- wetware, The Jargon File
- Azevedo et al., Equal numbers of neuronal and nonneuronal cells, J. Comp. Neurol., 2009, as reported in Herculano-Houzel, The Human Brain in Numbers
- Eighty-six billion and counting: do we know the number of neurons in the human brain?
- Balasubramanian, Brain power, PNAS, 2021
- Jordan et al., Open and remotely accessible Neuroplatform for research in wetware computing, Frontiers in Artificial Intelligence, 2024
- Kagan et al., In vitro neurons learn and exhibit sentience when embodied in a simulated game-world, Neuron, 2022
- Australian startup Cortical Labs unveils world's first commercial biological computer, DatacenterDynamics