Orient commands allow you to move and rotate your object in one command. In orient it transforms an object using 2 vectors. In orient3pt it transforms an object using 2 planes defined by 3 points.

orient command is primarily used in TOP or other elevation views.rectangle to match one edge of a triangle.
rectangleorientReference point 1 and Reference point 2. This is the first and second point on your rectangle defining your first vector.
Target Point 1 and Target Point 2 . These are the first and second point of your second vector.
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💡 Rhino 6 got smarter. It now adds little dots to help you identify reference and target points.
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Orient3pt takes regular orient a step further by defining your transformation with a plane rather than a vector.move and Rotate3D your object in one command. Very powerful!