After you pushed content using git or the editor, GitBook.io will start different builds:
- website: it will generate the website
- json: il will extract metadata about the book (summary, introduction, ...)
- epub: it will generate the epub download
- pdf: it will generate the pdf download
The Activity tab on your book let you follow the evolution of your builds.
When clicking the link "logs" for a build, you can access a details page for it. This page will let you see the output of the build process.
If your build failed, you can use the logs to debug the issue and publish a fixed content.