ZEPL Explore is a place for sharing ZEPL notebooks. As long as the notebook is set as Published(a.k.a Public), you can get the public URI and anyone(even non-ZEPL users) can see the notebook.
ZEPL has number of showcases available.
You can label your notebook with one of the showcase tags, so it will appear under particular showcase section inside Explore page.
If you select the showcases when you set your notebook to Published(a.k.a Public) mode, the notebook will be added under that showcase. Now you can show off awesome notebooks through the ZEPL!