I'am a dutchman so my native language isn't english. I am studying the Gertboard manual, because i have bought one, so that when i ask questions in forums on internet i don't get the answer 'RTFM'. But now i have a question about the manual. In the beginning of chapter Buffered I/O, LEDs, and Pushbuttons on page 14 and 15 in the first pargraph above Figure 8 is said "an output from the Gertboard is an input to the Raspberry Pi, and so the input jumper must be installed".
I think that is ment here that when you use one of the I/O pins of the Gertboard above the LEDs as an 'Input', the buffer 74xx244 from the gertboard act as an 'output' to an Raspberry Pi input pin. So an Input on the Gertboard is an Input on the Raspberry Pi.
Raspi-input o<---<|buffer|<----o< Gertboard-input.
I hope that i am thinking right, a bit confused.
And yes the paragraph under figure 8 explains it some more, but I was stuck with just the last sentence in the first pargraph