If you use iBooks Author, you can distribute to friends and family, either by exporting it as a pdf,but you lose any interaction you may have built in. Or you can export your completed book and by using a Cloud service like Dropbox and emailing a link to the file to those you wish to have the book. They in turn download the file and if they have a Mac with Mavericks installed, the open iBooks app and drag the book into it, and you can also sync yo iPad or...
This same process can be applied to those with iPads and the Dropbox (or other cloud service) by selecting to open the file in iBooks.