Hello dear CATIA Buildings&Infrastructure community,

I am so sorry to bother you like this but I need some help to better understand how to use this software and to improve my skills. I tried looking things up online but I couldn't find many informations about these "types". What are they for?

This is probably a silly question, but any help is appreciated. If it makes things better, you can direct me towards some useful pages for beginners, wikis and lessons...thanks.