Logic is used to identify spam comment submissions. No user interaction is required. The spam blocking mechanisms work transparently behind the scenes. Most visitors, e.g. humans, will require longer than a few seconds to read a post and comment so any comments submitted within a short time threshold are identified as spam. Comments containing a large number of links are flagged as spam. The plugin uses an encrypted code and a honeypot to filter robotic submissions. All field names added by the plugin are randomized to prevent detection based on a source code signatures.
The plugin also blocks spam messages submitted through the WordPress Contact Form Plugin.