You can use planes to sketch, to create a section view of a model, for a neutral plane in a draft feature, and so on. Click View, RefGeom, Ref Plane to toggle the display of reference planes.
To create a construction plane:
Click Plane(Reference Geometry toolbar) or click Geometry, Reference Geometry, Reference Plane.
In the dialog , select the type of plane you want to create and the items to create the plane:
Parameters. Create a plane by an origin point and a normal vector. You can also sketch ref-planes when "Sketch" is checked.
Throu Line/Pnt. Creates a reference plane passing the selected point and the selected line.
Normal/Pnt. Creates a reference plane which passes the selected point and normals to the selected line.
3 Point. Create a plane passing through 3 selected points.
2 Point. Create a plane normal to a virtual line segment built by 2 points.
Equation. Create a plane by equation. You can also define any point which the plane should pass through.