What is the basic theme of organisation in the periodic table?

Question

Philoid · Accepted Answer

In the early part of the 18^th century, only a few elements were known and hence it was very easy to remember the physical and chemical properties of such elements. But with discovery of new elements, it became practically impossible to remember the properties of all the elements.

Hence the need aroused for arranging the elements in form of a table or a chart where elements with same properties can be grouped together so that no confusion arises while dealing with elements and also true knowledge can be obtained about a particular element.