# parent_type var

Source: https://ref.dm-lang.org/datum/var/parent_type

### Default value
> The path of the object definition that contains this one.

This variable is set at compile-time to specify the inheritance of an object type. Normally, a new type of object inherits its variables and procedures from the object type that contains it. For example:

```dm
obj
   var
      weight
      color
   sword //parent type of 'sword' defaults to /obj
      weight = 30
      color = "black"
```

Explicitly setting the parent type allows you to put the object definition any place you want. That often means putting it at the top "root" level. Example:

```dm
Armor
   parent_type = /obj
   var
      strength
   plate //parent type is /Armor, which in turn inherits from /obj
      weight = 100
      color = "rusty"
      strength = 10
```

If you don't specify the parent_type for an object defined at the top level, it defaults to [/datum](https://ref.dm-lang.org/datum/index.md), which (with just a couple exceptions) is the ultimate ancestor of all object types. You could use that fact to define procedures or variables that you need all of your objects to share.

```dm
datum
   proc/Copy(datum/O)

MyType
   var
      foo
   Copy(MyType/O)
      foo = O.foo
      return ..()
```