how is serial.println working? Where is it printing?

Projects General Guidance
1

When i use C++ I known printf is printing on the output windows on my screen.
Here with arduino, I don't find any output window.
Where is it printing?
I am under windows XP.
Best regards
Paul

3

It sends the output to your serial monitor, your PC or dumb terminal. Could be set to send to anything that has a comm port provided that the baud and bit are set correctly.

4

Serial.println("Hello World") is sending the text in "" to the monitor of your PC and jumps to the next line
Serial.print("Hello World") sends the text to the monitor and the (invisible) cursor is sitting directly after the last character

e.g.:
Serial.println("Hello World");
Serial.println("Next line");
will result into:
Hello World
Next Line

whereas
Serial.print("Hello World");
Serial.print("Next line");
will give you:
Hello WorldNext Line