> For the complete documentation index, see [llms.txt](https://help.trikset.com/llms.txt). Markdown versions of documentation pages are available by appending `.md` to page URLs; this page is available as [Markdown](https://help.trikset.com/en/studio/programming-visual/expression-syntax/sensory-variables.md).

# Sensor variables

Besides [constants](/en/studio/programming-visual/expression-syntax/const.md), in TRIK Studio reserved variables are available that store the values ​​of the readings of sensors connected to the corresponding ports.

These values ​​can be assigned to variables and used in mathematical expressions.

Variables have the form

```lua
sensor<port name>
```

For example, `sensorA1` for TRIK or `sensor1` for Lego NXT.

A complete list of sensor variables is provided in sections for specific platforms:

* [TRIK](/en/trik/programming-visual/sensory-variables.md).
* [LEGO EV3](/en/ev3/sensory-variables.md).
* [LEGO NXT](/en/nxt/sensory-variables.md).