What is a binary tree?
A binary tree 'T' is described as
A finite set of elements, known as nodes, such that: either (i) or (ii) happens:
(i) T is empty (known as the 'null tree' or 'empty tree')
(ii) T having a distinguished node R, known as the 'root' of T and the remaining nodes of 'T' form an ordered pair of the disjoint binary tree Tl and T2.
If 'T' having a root 'R' then the two trees Tl and T2 are known as, the 'left' and 'right' sub trees of R, respectively.