A chemist spends a lot of time trying to understand matter and the changes that it can undergo. Matter is made up of what we call elements. Elements are to chemistry what the letters of the alphabet are to our language and the formation of words. The periodic table of elements has been developed to classify elements for us. Examples of elements include hydrogen, carbon, nitrogen, and oxygen.
Atoms are the smallest part of an element.
They can combine with other atoms to form molecules, just as words are composed of the letters of the alphabet. All that makes life beautiful, all that makes life go on when it is not beautiful, both living things as well as material possessions have molecular basis. There are at least as many different molecules as there are different words in the dictionary.