the diary for two...

[sodapple]

みなさん：

I don't know what is the name for this shared diary.
This shared diary I have seen it only in Japanese dramas,
That is common in Japan?
Or that is a thing that only happens in the dramas?
What is its real name for this shared diary?
I think that there is special notebooks for this, right?

Ah! sorry for this last question: What things do they write in there?

ありがとう！

[hatch_jp]

交換日記 （こうかん にっき kohkan nikki）？
http://en.wikipedia.org/wiki/Exchange_diary

[JonB]

how topical I saw two girls doing this on the bus the other day - now I know what is going on!