Syntax Differences

Just a quick noobie question..

I've noticed some differences in the syntax used to perform certain tasks... Like:

std::cout << "bla bla bla".....
// versus
cout << "bla bla bla".....

//or

std::cin >> blablabla....
//versus
cin.get(blablabla)...

Is there any specific reason for using one over the other?
It seems as though they achieve the same task...?