A plane is a flat surface that you can create a sketch on. Onshape documents start with three planes already existing: front, right, & top.
The origin is the dot in the middle of the three planes. This is the only thing on Onshape that will never move. It is the point where all 3 planes intersect.
A part studio is the space that is opened when you first create a document. This is the area that you can create sketches and 3D objects.
The feature list is the area on an Onshape document that shows you everything that exists in the current part studio that you are working in.
When creating a sketch, you have to select a sketch plane. This is the surface that you will be drawing on. You may choose a plane or a side of a 3D object as your sketch plane.
The extrude tool is a way to make a 2-dimensional object (such as a sketch) 3-dimensional.Â
You must have a sketch before you can extrude anything!
A fully-defined sketch is a sketch that is completely dimensioned or "relationships" to the origin or another fully-defined sketch. Fully-defined sketches will have all black lines and points.
An over-defined sketch is a sketch that has too many dimensions or relationships to fully-defined sketches. These sketches will turn red, highlighting the reasons why the sketch is over-defined.