Some philosophers say that naming something is the first step toward figuring out what makes that thing different from all the other things in the world. In a SketchUp 3D model, this idea isn’t some wishy-washy concept. When you use the Classifier to embed data into groups or or components, those groups or components become objects. When objects have names, descriptions, and so on, you can manage the details about all the classified objects.

In SketchUp, layers control your geometry’s visibility.

In SketchUp, the Outliner enables you to view a model’s groups and componentsgroups, components, and section planes as a hierarchical tree. With the Outliner, you can

As you create 3D models in SketchUp, you create an entity whenever you draw a line or face. Combining lines and faces into a group or component creates a special group or component entity. Each entity in a model has attributes, such as its measurement, the layer it’s on, and more. If an entity is a component, then it has an instance and might be a solid (or not) or have other attributes, such as an IFC type. Depending on what you’re doing in SketchUp, you might need to know or change an entity’s attributes. To do so, look in the Entity Info panel:

SketchUp components enable you to reuse objects. For example, pretty much every building has at least one door and window. Instead of modeling these common objects, you can insert a component that someone else has already made. Like all geometry in SketchUp, a component is still made of edges and faces. The edges and faces are simply part of a special component group. (You can also create components to reuse your own geometry, but that’s covered in Developing Components and Dynamic Components.)

Can you imagine Johannes Gutenberg, inventor of the printing press, learning how to create 3D models in SketchUp? Hopefully, he’d like the way SketchUp advances his groundbreaking invention — especially the text that moves and (in some cases) updates as you work on your model. In SketchUp, you can add four types of text, each depicted in the following figure:

With SketchUp’s Solid tools, you can create new shapes by combining or cutting one shape with another, making it easy to model an outer shell or joinery.