want to know how input and output components work and how to detect if theres one not working

Question

i have to write a test for work and i didnt understand the meaning of how input and output works on the components they were all connected and lines running from one another and you had to know wich one wasnt working and i didnt understand anything they were saying on how it works because it wasnt explained to me

Answer 1

?????????? yu hav a masheen ????

& thro sumthun intu a hopper

& sumthun come out the other side ?????????