How is the implementation of pipes in a OS
Like message passing.  The kernel allocates a private buffer for storing the data that has been sent and is waiting to be delivered to the recipient.

For more details, see:


http://www.slideshare.net/divyekapoor/linux-kernel-implementation-of-pipes-and-fifos
http://linux.omnipotent.net/article.php?article_id=12504&amp;page=-1


In the future, please do more research before asking.  We expect you to do some serious research before asking.  The links above showed up in the first few responses to my first Google search, which is a hint that you should have done more research on your own.