# entity_api_types.h ## Index
`struct tm_entity_t`
`struct tm_component_type_t`
## API
### `struct tm_entity_t`
~~~c typedef union tm_entity_t { // Internal -- represents an entity with a slot index and a generation counter that is incremented // when the slot is reused, allowing us to use the entity as a weak reference. struct { uint32_t index; uint32_t generation; }; // Entity as uint64_t for simple comparison and assignment. uint64_t u64; } tm_entity_t; ~~~ Represents an entity.
### `struct tm_component_type_t`
Represents a component type. ~~~c typedef struct tm_component_type_t { // The index of the component type in the entity context. uint32_t index; } tm_component_type_t; ~~~