> For the complete documentation index, see [llms.txt](https://docs.enercalc.com/llms.txt). Markdown versions of documentation pages are available by appending `.md` to page URLs; this page is available as [Markdown](https://docs.enercalc.com/e3d-user-manual/model-entities/toc161394014/toc161394015.md).

# Global Coordinate System

Understand the global Cartesian coordinate system and which inputs and outputs reference it.

![](https://560001759-files.gitbook.io/~/files/v0/b/gitbook-x-prod.appspot.com/o/spaces%2FWNe8U6EBBBdUJHdb2X9G%2Fuploads%2Fgit-blob-2dac3c9b090c32c06a424d274af45e2c74dbabde%2FFASTFR~1_img221_was_BMP.jpg?alt=media)

The global coordinate system is a fixed Cartesian system that is used for entire model. The three axes are denoted by capital letters X, Y and Z. They follow the right-hand rule. By default, that is, when a model is not rotated for viewing purpose, the X axis points from left to right (horizontal), the Y axis points from bottom to top (vertical), and the Z axis points from screen to out of screen (perpendicular to screen).

The global coordinate system is used in the following input:

* nodal coordinates, nodal loads
* degrees of freedom related to nodes, supports and springs
* self weights
* point, line, and surface loads on members and finite elements \[may also be specified in the element local coordinate system]

The global coordinate system is used in the following output:

* nodal displacements
* support and spring reactions
* brick stresses


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