This allows you to see what you're working on in a much cleaner way than leaving everything visible.

You can place any type of object into VisGroups and label them so that you can hide them or reveal them as a group. VisGroups are a way to organize your level. You can place lights, props (models) and items using the Object bar. While brushes are the basic building blocks of levels, entities placed with the Object bar are pretty much everything else. Used to place objects in your level that are not simple geometry. The Texture bar allows you to see the currently selected texture and to browse for other textures by going into the Browse.

Solids - You will select individual components even if it has been joined with others to make one object.

Objects - You will select an entire object even if it consists of more than 1 component.

Groups - You will select the whole sets of objects that have been grouped together.

The Selection Mode bar switches between modes of selecting objects in the map: The Tools bar switches the editor to different modes that allow you to select, build, place, texture, and manipulate different objects in your level. These bars across the top of the window contain a variety of buttons to control the viewing of objects in the map, as well as controls for the grid and snapping tools. You will learn how to use these items throughout this tutorial, so don't worry about learning about how they all function quite yet. Here is a basic description of the Hammer interface.

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