Once any dynamic item has been simulated and the motions cached, including both rigid bodies and particles, the cache remains as part of the saved scene until it is invalidated or deleted. Modo can render either of these dynamic items directly, using the cached values, but in cases where Modo may not be the final destination (or you want to apply modifiers to the item), you can convert the dynamics cache into keyframes for rigid bodies and geometry for particles. This conversion process is called baking.
Rigid bodies that have been simulated and cached can be converted to animated keyframes, retaining all the motion and nuance of the actual simulation, using the standard Bake Animation command. This is found in the menu bar under Animate > Bake.... To apply it, simply select the target item(s) and run the command. Keyframes are generated for each frame in the Timeline, based on the Start and End frame values entered. Baked dynamic items retain their dynamic features. To disable this, in the menu bar, click Dynamics > Make Un-dynamic. This removes any tags from the item that would include it in future simulations. For more information on the Bake Animation command, see Tools and Commands.
Sometimes dynamics are used to simply place items in a scene, and the actual animated movement of the elements is unnecessary (such as filling a bowl with fruit). In this case, you can simply bake the current item position into the Position and Rotation transform of the item with the command Dynamics > Bake Dynamics Transforms. The current Timeline position is used for the defined values, so make sure it is located at the desired position. This also retains the dynamic features.
Particles that have been simulated and cached can be converted to several different formats that provide some powerful options. With the target particle simulation item selected in the Items list, apply the menu bar command Dynamics > Convert Particle Cache > Particles to Mesh. This converts the particle positions at each frame into a Mesh Item that is parented to the particle simulator. This layer contains a series of continuous edges (also considered two-point polygons), representing the paths for each individual particle that you can directly modify using any of Modo's modeling tools, including the particle sculpting tools. Once modified to your liking, these paths can then be converted back into the cache as particle paths, replacing the previous values. This is done with the command Dynamics > Convert Particle Cache > Particles from Mesh. This allows for ultimate control over every single particle in a simulation. The Auto Update option keeps the cached values continuously updated as you modify the resulting mesh layer.
Sometimes it can be beneficial to simply use the simulation tools to generate particles for still images. In such cases, you can select the desired frame of a cached particle simulation along the Timeline and apply the menu bar command Dynamics > Convert Particle Cache > Particles to Cloud, converting the current positions into a Mesh Item, containing static vertices representing each individual particle from the simulation. The resulting layer can be assigned as a point source to the many particle-related effects that Modo offers, such as Replicators, Blobs or Volumes.
Another interesting effect is the command Dynamics > Convert Particle Cache > Particles to Curves that generates a similar output to that of the Particles to Mesh command, however the resulting paths are curves that can be rendered using the Render Curves option of the Mesh Item. When combined with gradients controlling thickness and color, and the addition of displacements, an entire world of creative possibilities opens up.