What is a “package” in terms of PHP Depend?

Question

On the http://pdepend.org/documentation/handbook/reports/overview-pyramid.html it is said that:

NOP - The Number Of Packages metric counts the packages within the analyzed software system.

How the "package" is determined? Is it just @package phpdoc attribute value?

Answer 1

It is a duplicate of PHP Depend and @package-annotations

Since community haven't voted for close and I don't want to have 1 not accepted questions - I answer myself.