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docs/internal-architecture.md

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+## Collector internal architecture
+There are a few resources available to understand how the collector works:
+### [Startup Diagram](#startup-diagram)
+### [Architecture Docs](https://opentelemetry.io/docs/collector/architecture/)
+### [Important Files](#important-files)
+### Startup Diagram
+```mermaid
+flowchart TD
+    A("`**command.NewCommand**`") -->|1| B("`**updateSettingsUsingFlags**`")
+    A --> |2| C("`**NewCollector**
+    Creates and returns a new instance of Collector`")
+    A --> |3| D("`**Collector.Run**
+    Starts the collector and blocks until it shuts down`")
+    D --> E("`**setupConfigurationComponents**`")
+    E -->  |1| F("`**getConfMap**`")
+    E ---> |2| G("`**Service.New**
+     Initializes telemetry, then initializes the pipelines`")
+    E --> |3| Q("`**Service.Start**
+    1. Start all extensions.
+    2. Notify extensions about Collector configuration
+    3. Start all pipelines.
+    4. Notify extensions that the pipeline is ready.
+    `")
+    Q --> R("`**Graph.StartAll**
+    Calls Start on each component in reverse topological order`")
+    G --> H("`**initExtensionsAndPipeline**
+     Creates extensions and then builds the pipeline graph`")
+    H --> I("`**Graph.Build**
+     Converts the settings to an internal graph representation`")
+    I --> J("`**createNodes**
+     Builds the node objects from pipeline configuration and adds to graph.  Also validates connectors`")
+    I --> K("`**createEdges**
+     Iterates through the pipelines and creates edges between components`")
+    I --> L("`**buildComponents**
+     Topological sort the graph, and create each component in reverse order`")
+    L --> M(Receiver Factory) & N(Processor Factory) & O(Exporter Factory)
+```
+### Important Files
+Here is a brief list of useful and/or important files that you may find valuable to glance through.
+#### [collector.go](../otelcol/collector.go)
+This file contains the main Collector struct and its constructor `NewCollector`.
+
+`Collector.Run` starts the collector blocks until it shuts down.
+
+`setupConfigurationComponents` is the "main" function responsible for startup - it orchestrates the loading of the 
+configuration, the creation of the graph, and the starting of all the components.
+
+#### [graph.go](../service/internal/graph/graph.go)
+This file contains the internal graph representation of the pipelines.
+
+`Build` is the constructor for a Graph object.  The method calls out to helpers that transform the graph from a config
+to a DAG of components.  The configuration undergoes additional validation here as well, and is used to instantiate
+the components of the pipeline.
+
+`Graph.StartAll` starts every component in the pipelines.
+
+`Graph.ShutdownAll` stops each component in the pipelines
+
+#### [component.go](../component/component.go)
+component.go outlines the abstraction of components within OTEL collector.  It provides details on the component 
+lifecycle as well as defining the interface that components must fulfil.
+
+#### Factories
+Each component type contains a Factory interface along with its corresponding NewFactory function.
+Implementations of new components use this NewFactory function in their implementation to register key functions with 
+the collector.  For example, the collector uses this interface to give receivers a handle to a nextConsumer - 
+representing where the receiver can send data to that it has received.