Which system am I running?

[battles]

I read that Snort can run as an NIDS (network intrusion detection system) or run as an NIPS (network intrusion prevention system).  I am not clear about this.  Can Snort run both at the same time?  How do I determine which system I am running?

[divsys]

Best to ask over in the Packages-IDS/IPS subforum https://forum.pfsense.org/index.php?board=61.0, dedicated to exactly those type of questions.