what is the meaning of iostream in c++
Input/output (C++) C++ input/output streams are primarily defined by iostream, a header file that is part of the C++ standard library (the name stands for Input/Output Stream). In C++ and its predecessor, the C programming language, there is no special syntax for streaming data input or output. Instead, these are combined as a library of functions. Like the cstdio header inherited from C's stdio.h, iostream provides basic input and output services for C++ programs. iostream uses the objects cin, cout, cerr, and clog for sending data to and from the standard streams input, output, error (unbuffered), and log (buffered) respectively. As part of the C++ standard library, these objects are a part of the std namespace.[8]
printf format string "Printf" is the name of the most-used C output function, and stands for "print formatted". Printf format strings are complementary to scanf format strings, which provide formatted input (parsing). In both cases these provide simple functionality and fixed format compared to more sophisticated and flexible template engines or parsers, but are sufficient for many purposes.