update Resource spec based on the move to the SDK and named tracers (o…

…pen-telemetry#421)

* update Resource spec based on the move to the SDK and named tracers

* Update specification/sdk-resource.md

Co-Authored-By: Tyler Yahn <[email protected]>

* Update specification/sdk-resource.md

Co-Authored-By: Tyler Yahn <[email protected]>

* Update specification/sdk-resource.md

Co-Authored-By: Tyler Yahn <[email protected]>

* provide example of what the entity producing telemetry means

* Update specification/sdk-resource.md

Co-Authored-By: John Watson <[email protected]>

Co-authored-by: Tyler Yahn <[email protected]>
Co-authored-by: John Watson <[email protected]>
Co-authored-by: Bogdan Drutu <[email protected]>

specification/sdk-resource.md

@@ -1,25 +1,30 @@
 # Resource SDK
 
-A [Resource](overview.md#resources) represents the entity producing telemetry.
-The primary purpose of resources as a first-class concept in the API is
+A [Resource](overview.md#resources) represents the entity producing
+telemetry. For example, a process producing telemetry that is running in a
+container on Kubernetes has a Pod name, it is in a namespace and possibly is
+part of a Deployment which also has a name. All three of these attributes can be
+included in the `Resource`.
+
+The primary purpose of resources as a first-class concept in the SDK is
 decoupling of discovery of resource information from exporters. This allows for
 independent development and easy customization for users that need to integrate
-with closed source environments. API MUST allow for creation of `Resources` and
+with closed source environments. The SDK MUST allow for creation of `Resources` and
 for associating them with telemetry.
 
 When used with distributed tracing, a resource can be associated with the
-[TracerSdk](sdk-tracing.md#tracer-sdk). When associated with `TracerSdk`, all
-`Span`s produced by the `Tracer`, that is implemented by this `TracerSdk`, will
+[TracerProvider](sdk-tracing.md#tracer-sdk). When associated with a
+`TracerProvider`, all `Span`s produced by any `Tracer` from the provider will
 automatically be associated with this `Resource`.
 
 When used with metrics, a resource can be associated with the
-[MeterSdk](sdk-metrics.md#meter-sdk). When associated with `MeterSdk`, all
-`Metrics` produced by this `Meter`, that is implemented by this `MeterSdk`, will
-automatically be associated with this `Resource`.
+[MeterProvider](sdk-metrics.md#meter-sdk). When associated with a `MeterProvider`,
+all `Metrics` produced by any `Meter` from the provider will automatically be
+associated with this `Resource`.
 
 ## Resource creation
 
-The API interface must support two ways to instantiate new resources. Those are:
+The SDK must support two ways to instantiate new resources. Those are:
 
 ### Create
 
@@ -66,7 +71,7 @@ In addition to resource creation, the following operations should be provided:
 
 ### Retrieve attributes
 
-The API should provide a way to retrieve a read only collection of attributes
+The SDK should provide a way to retrieve a read only collection of attributes
 associated with a resource. The attributes should consist of the name and values,
 both of which should be strings.