# Buildup simulation inputs

PyECLOUD reads its simulation settings from Python-style `.input` files.
The simulation input file selects the machine, beam, and secondary emission
input files. Additional cloud files configure simulations with multiple clouds.

Parameters marked *Optional* can be omitted and take the stated default. Example values are
illustrations, not recommended settings.

```{toctree}
:maxdepth: 1

simulation
machine
beam
secondary-emission
multiple-clouds
```

The {download}`original reference manual <../legacy_tex/reference/reference.pdf>` can be used as a reference
when using PyECLOUD versions older than v8.9.0.