Yes, and with at few small difference depending on type of operating system.
Microsoft Windows: The P9 Agent runs two services: ”Panorama9 Agent” and ”Panorama9 Agent Updater” (which automatically keeps the agent updated). See here for information about how to start/stop the P9 services.
Mac OS X: The P9 Agent runs two privileged Launch Agents: "com.panorama9.daemon" and "com.panorama9.updater" (which automatically keeps the agent updated). See here for information about how to start/stop the P9 LaunchDaemon.
Linux: The P9 Agent runs as a non-privileged daemon: "p9-agent". A daily cron job keeps the Agent updated. See here for information about how to start/stop the P9 daemon.
The Agent takes up approximately 15 MB of disc space, less than 20 MB of memory on average and almost no processor or network bandwidth usage.