Prototypically a volitional action, though not necessarily #004.
A volitional Means will often modify an intended result, though the outcome can be unintended as well #003.
Open the door by turning the knob. 001
They retaliated by shooting/with shootings. 002
The owners destroyed the company by growing it too fast. 003
Chlorophyll absorbs the light by transfer of electrons. 004
Means is similar to Instrument, which is used for causally supporting entities and is a kind of Participant.
Contrast with Explanation, which characterizes why something happens. I.e., an Explanation portrays the secondary event as the causal instigator of the main event, whereas Means portrays it merely as a facilitator.
Contrast also with Manner. Both Means and Manner elaborate on the how of an event; however, a Manner describes a quality of the main event, rather than specifying a facilitating event.