The periodic table of chemical elements, often called the periodic table, organizes all discovered chemical elements in rows (called periods) and columns (called groups) according to increasing atomic ...

and all the elements in group 0 are unreactive non-metals. The zigzag, staircase, line in the diagram of the periodic table above separates the metals, on the left, from non-metals, on the right.

Scientists have found that our bodies need 28 different elements to function properly. These are almost one-quarter of the periodic table and are mainly found in the first four periods.