Are StaticMeshes usually comes with collision?

from link text

By default, there is no collision set
on this mesh. Without collision, the
player would be able to walk through
the mesh and if the mesh simulates
physics, the mesh would simply fall
through the world as soon as play
began. You can test this by placing
this mesh into your level before
setting up collision and playing.

I create a new actor and when I add a staticmesh to it, it already able to block my character, without the need of adding a collision component to it.

Does it mean that only those whose collision doesn’t setup using the editor are the only ones who needed to be set explicitly?

The collisions can also be set on the Static Mesh Edit Window, by double clicking on the Static Mesh asset.

Then when adding this Static Mesh either as an actor or as a component these will be the default collision configurations.

If you want to see collision info on Play Mode, type “show collision” on the Console on the Output Log