The periodic table is a tabular array of the chemical elements organized by atomic number, from the element with the lowest atomic number, hydrogen, to the element with the highest atomic number, oganesso

Elements are arranged in the increasing order of atomic numbers. Elements in the modern periodic tableare arranged in 7 periods and 18 groups. Horizontal rows are called periods and vertical columns are called groups. Element are placed in period based on the number of shells in their atoms.

The most important examples of elements in everyday life are carbon, hydrogen, oxygen and apart from these chlorine, sulphur, calcium, iron, phosphorus, nitrogen, sodium, and potassium are also essential for everyday life.