This is a crowd behavior node, but you can also use it on regular particles (see the Output attribute parameter).
This node has a Force parameter, which controls the base speed of the wander, and Amplitude, which controls the size of the changes to the base speed. So, for example, high Force and low Amplitude would give fast motion with small deviations, while low Force and high Amplitude would give overall slower motion but with big swings in direction and speed.
When this is off, the node will have no effect. You can animate this to turn the behavior on or off at different times.
Only modify a certain group or groups out of all agents/particles. You can name groups of agents using the Group name parameter on the Crowd Source geometry node.
Available when Output attribute is "Crowd steerforce". This number is used by the crowd solver to normalize and scale multiple forces that apply to an agent.
Base strength of the wander force.
Whether to use 2D noise or 3D noise.