Metals, non-metal and noble gases are the three categories useful for classifying the elements in periodic table.
Step-by-step explanation:
Elements are defined as a vertical group and a horizontal period in periodic table. Metals, non-metal and noble gases are the three categories useful for classifying the elements in periodic table.
A large number of elements in periodic table flow under the Metals category. Non-metal in the table are mostly gaseous. Noble gases in the table are colorless and non-reactive.