For more information on the particle surface node, see the Particle SOP node help.
When to use a real particle network
Large number of local variables to represent particle attributes.
Control over attribute manipulation and inheritance.
Grouping of points based on rules or collisions.
Support for per-particle rotation and instanced geometry.
More birthing options.
Multiple collision objects/attractors.
Ability to customize a particle system’s behavior with networks of pops.
Ability to write custom POPs with the HDK.
How to create a real particle network
There is a tab on the shelf called Create Particles which allows you to create complex particle systems by simply clicking a button.
For more information on the different types of particle systems and how to create them see the following help pages: