# Coordinate system

Tekla Structures uses two coordinate systems: the global and the local coordinate system. The local coordinate system is also known as the work plane.

## Global coordinate system

The green cube symbol represents the global coordinate system and lies at the global point of origin (x=0, y=0, z=0). The global coordinate system is static and it cannot be changed.

Do not place the model far away from the origin. If you create model objects far away from the origin, snapping to points in the model views may become inaccurate. The further away from the origin you model, the less precise all computations become.

If you need to use another coordinate system for inserting reference models or exporting IFC models, you can use base points. When you use base points, you can keep the coordinates small and locate the model wherever needed.

## Local coordinate system (Work plane)

The work plane represents the local coordinate system. Most of the commands that are dependent on the coordinate system use the work plane coordinates. For example creating points, part positioning, and copying always comply with the work plane coordinate system. The coordinate symbol, which is located in the lower right corner of the model view, follows the work plane.

The work plane is model specific, so it is the same in all views. The red work plane arrow symbol shows the xy plane. The z direction follows the right-hand rule.

You can change the local coordinate system by shifting the work plane. The work plane also has its own red grid, which can be used for positioning parts. You can show or hide this grid as needed.

To control which work plane or base point you currently have in use in the model, use the work plane handler toolbar.