What are the 4 categories included in the Periodic Table?

Question

There are many ways to categorize elements. I am uncertain how you got just four.

The Originator of the four concepts did it this way...

http://elements.vanderkrogt.net/chemical_symbols.html

Maybe your teacher is looking for these four: Nonmetals, metals, noble gases, and rare earths. Or nonmetals, metals, noble gases, and metalloids.

Thanks!
Do you know the group numbers of the periodic table or know a site that does?

Go to www.webelements.com amd click on the pro version.

Answer 1

Do you guys have a poem for group 17 of the periodic table