Based on the electronic configuration the elements are classified as metals, non metals and metalloids.
Explanation:
Periodic table consists of three major parts.
The left side consists of metals and the right side consists of non-metals and here Hydrogen element is the exception and in between those two regions we have metalloids, which has the dual character of both metals and non metals.
These elements can be grouped by means of its chemical properties and also due to its outermost electronic configuration.
If the valence shell electrons are same they are categorized under same group.
