Definition : 

• Catenation can be defined as self-linking of atoms of an element to form chains and rings.
• This definition can be extended to include the formation of layers ( two dimensional catenation ) and space lattices ( three dimensional catenation ).
• It depends upon bond energy, size and bond length between the atoms of the same element.

Subtopic : Why Carbon shows highest catenation property ? 

• Carbon shows the property of catenation as it is small in size and has the ability to form stable covalent bonds with other carbon atoms to form a chain-like structure.
• The bond energy between the C-C bond is very high which enables them to form a long chain of C-C stable bonds. 

Figure : Electronic Configuration of 

                         Carbon