endl and flushing the buffer

Question

In the C++ primer book, in chapter (1), it mentions the following:

endl is a special value, called a manipulator, that when written t

Answer 1

Output is generally buffered before it's written to the intended device. That way, when writing to slow to access devices(like files), it doesn't have to access the device after every single character.

Flushing means emptying the buffer and actually writing it to the device.