How to set global types \ aesthetic templates?

[giuliogcantone]

I started today to learn this package.

I understand that "type" is a sort of wrapper for node(aes) in the sense that "type = 'a' " tells to the program to apply the node(aes) associated to the template type "a".

I cannot find the command to set global types. In all the guides, types are always mentioned but they are never explained.

Maybe "type" is just a extra group tag with no practical effect. If that's the case, is there a fast way to add a aesthetic template for groups of nodes?