A Static RigidbodyA component that allows a GameObject to be affected by simulated gravity and other forces. More info
See in Glossary 2D is designed to not move under simulation at all. If anything collides with it, a Static Rigidbody 2D behaves like an immovable object (as though it has infinite mass). It is also the least resource intensive Body TypeDefines a fixed behavior for a 2D Rigidbody. Can be Dynamic (the body moves under simulation and is affected by forces like gravity), Kinematic (the body moves under simulation, but and isn’t affected by forces like gravity) or Static (the body doesn’t move under simulation). More info
See in Glossary. A Static body only collides with Dynamic Rigidbody 2Ds.
Note: Having two Static Rigidbody 2Ds collide is not supported, since they are not designed to move.
Aside from setting the Rigidbody 2D to the Static Body Type, there is another scenario where a Static Rigidbody 2D is created. This is when a GameObjectThe fundamental object in Unity scenes, which can represent characters, props, scenery, cameras, waypoints, and more. A GameObject’s functionality is defined by the Components attached to it. More info
See in Glossary with a ColliderAn invisible shape that is used to handle physical collisions for an object. A collider doesn’t need to be exactly the same shape as the object’s mesh - a rough approximation is often more efficient and indistinguishable in gameplay. More info
See in Glossary 2D component does not have a Rigidbody 2D component at all. All Collider 2Ds without a Rigidbody 2D component are internally considered to be attached to a single hidden Static Rigidbody 2D component.
This means that you are able to create a large number of Static Collider 2Ds as you do not have to add a Rigidbody 2D component for each individual GameObject. Both methods of creating Static Collider 2Ds have their advantages, depending on the scenario.
If an individual Static Collider 2D needs to be moved or reconfigured at runtime, then add a Rigidbody 2D component and set it to the Static Body Type, as it is faster to simulate the Collider 2D when it has its own Rigidbody 2D. If a group of Collider 2Ds needs to be moved or reconfigured at runtime, it is faster to have them all be children of the single hidden parent Rigidbody 2D than to move each GameObject individually.
Note: As stated above, Static Rigidbody 2Ds are designed not to move, and collisionsA collision occurs when the physics engine detects that the colliders of two GameObjects make contact or overlap, when at least one has a Rigidbody component and is in motion. More info
See in Glossary between two Static Rigidbody 2D objectsA 2D GameObject such as a tilemap or sprite. More info
See in Glossary that intersect are not registered. However, Static Rigidbody 2Ds and Kinematic Rigidbody 2Ds will interact with each other if one of their Collider 2Ds is set to be a trigger. There is also a feature that changes what a Kinematic body will interact with (see Use Full Kinematic Contacts for more information).