Escape sequence \f - form feed - what exactly is it?

\f is said to be the form feed. \t is a tab, \a is a beep, \n is a newline. What exactly is a form feed - \f? The following program

#include <iostream>
int main()
{
   std::cout << "hello\fgoodbye" << std::endl;  
}

prints hello then a female sign (an upside down holy hand grenade:) and then goodbye all on one line.

It skips to the start of the next page. (Applies mostly to terminals where the output device is a printer rather than a VDU.)

From wiki page

12 (form feed, \f, ^L), to cause a printer to eject paper to the top of the next page, or a video terminal to clear the screen.

or more details here.

It seems that this symbol is rather obsolete now and the way it is processed may be(?) implementation dependent. At least for me your code gives the following output (xcode gcc 4.2, gdb console):

hello
    goodbye