VL has 3 patch types that help you structure your documents:
Group patches simply allow you to create more space in a document by opening a new canvas. The groups name is merely used for human readability, vl doesn’t care about it at all. Create a group by typing "group" in the NodeBrowser. Groups can be nested.
A Category patch looks quite similar to the group, only its name has a meaning: The name appends itself to the category of its parent patch. That way you can build up any category hierarchy, that you then see in the NodeBrowser. Multiple category levels are allowed with dot notation. e.g. MyCat1.MyCat2 etc.
A Full Category patch is similar to the Category patch, only that it doesn’t add its category to the parent. By that you can place nodes in any category, regardless of the parent patch. It’s considered bad practice to do that, but is useful to add nodes to an existing category like Collections.Spread, for example. Multiple category levels are allowed with dot notation. e.g. MyParentCat.MySubCat etc.