Folks, remember this colorful table from our Science classes ? Just to refresh some dormant memory cells, this Periodic Table organizes the whole earth — if not the Universe — into an orderly array.
We learned that this world comprises of all kinds of elements, from lazy inert ones that do nothing, to aggressive ones which react angrily with almost anything that crosses their paths. Yet others with make rapport with consenting members in the neighbourhood near and far to form all kinds of bonds (ionic, co-valent, etc) resulting in myriads of compounds, including you and I.
Some extreme elements can also gang up with others to become radicals, when conditions are ripe & right.
Amazing to realize that the seeming randomness of the universe is indeed really quite systematic. Sherlock Holmes might be astounded.