Instructions: Given a passage and a question, find the answer to the question based on the passage. The answer should consist of only one word that lies in the span of only one of the sentences in the passage.
Input: Paragraph: The periodic table is a tabular arrangement of the chemical elements , ordered by their atomic number , electron configuration , and recurring chemical properties , whose adopted structure shows periodic trends . Generally , within one row ( period ) the elements are metals on the left , and non-metals on the right , with the elements having similar chemical behaviours being placed in the same column . Table rows are commonly called periods and columns are called groups . Six groups have accepted names as well as assigned numbers : for example , group 17 elements are halogens ; and group 18 are noble gases . Also displayed are four simple rectangular areas or blocks associated with the filling of different atomic orbitals .
Question: what is the name given to the rows in the periodic table

Output:
periods