What are manifests in Puppet?

The process of automating server provisioning using Puppet, a popular configuration management tool capable of managing complex infrastructure in a transparent way, using a master server to orchestrate the configuration of the nodes.

It is Xml file to use for configure connection application to server deployment.

Collection of Manifest makes up a  Module in Puppet which contains files and templates.

Puppet programs are called manifests. Manifests are composed of puppet code and their filenames use the .pp extension. The default main manifest in Puppet installed via apt is /etc/puppet/manifests/site.pp