I'm not really sure about namespaces, so I can't compare.
Manual explains :session this way:
The |:session| header argument starts a (possibly named) session for an
interpreted language where the interpreter’s state is preserved. All
code blocks sharing the same name are exectuted by the same interpreter
process. By default, a session is not started.
(fetched from: http://orgmode.org/manual/session.html)
On 28.12.2015 20:39, Lawrence Bottorff wrote:
That's the org mode version of namespaces, if I'm not mistaken.