What is a Friendship ?

Now-a-days everybody wants to make a friendship with
boys and girls, but what's the reason on behind it. Some
times it becomes a holy relationship and some times it
make an extra ordinary relationship we can call it only
physical attraction.........

But,
According to me it's defination would be as given below:-

"Friendship is a type of interpersonal relationship
that is found among humans and among animals
with rich intelligence, such as the higher mammals
and some birds. Individuals in a friendship or
relationship will seek out each other's company
and exhibit mutually helping behavior."