diff --git a/docs/concepts/concept-flows.md b/docs/concepts/concept-flows.md
index ff58925b1a1..626baaf3e4d 100644
--- a/docs/concepts/concept-flows.md
+++ b/docs/concepts/concept-flows.md
@@ -12,7 +12,7 @@ Our [examples](https://github.com/microsoft/promptflow/tree/main/examples/flex-f
 
 Thus LLM apps can be defined as Directed Acyclic Graphs (DAGs) of function calls. These DAGs are flows in prompt flow.
 
-A flow in prompt flow is a DAG of functions (we call them [tools](./concept-tools.md)). These functions/tools connected via input/output dependencies and executed based on the topology by prompt flow executor.
+A `DAG flow` in prompt flow is a DAG of functions (we call them [tools](./concept-tools.md)). These functions/tools connected via input/output dependencies and executed based on the topology by prompt flow executor.
 
 A flow is represented as a YAML file and can be visualized with our [Prompt flow for VS Code extension](https://marketplace.visualstudio.com/items?itemName=prompt-flow.prompt-flow). Here is an example `flow.dag.yaml`:
 
@@ -20,6 +20,17 @@ A flow is represented as a YAML file and can be visualized with our [Prompt flow
 
 Please refer to our [examples](https://github.com/microsoft/promptflow/tree/main/examples/flows) to learn how to write a `DAG flow`. 
 
+## When to use Flex or DAG flow
+
+`Dag flow` provides a UI-frienctly way to develop your LLM app, which has the following benifits:
+- **Low code**: user can drag-and-drop in UI to create a LLM app.
+- **DAG Visualization**: user can easily understand the logic structure of the app with DAG view.
+
+`Flex flow` provides a code-friendly way to develop your LLM app, which has the following benifits:
+- **Quick start**: Users can quickly test with a simple prompt, then customize with python code with Tracing visuliazation UI.
+- **More advanced orchestration**: Users can write complex flow with Python built-in control operators (if-else, foreach) or other 3rd party / open-source library. 
+- **Easy onboard from other platforms**: user might already onboard platforms like `langchain` and `sematic kernel` with existing code. User can easily onboard promptflow with a few code changes.
+
 ## Flow types
 
 Prompt flow examples organize flows by three categories:
diff --git a/docs/how-to-guides/develop-a-flex-flow/class-based-flow.md b/docs/how-to-guides/develop-a-flex-flow/class-based-flow.md
index 270b131d493..1fc0f156cbd 100644
--- a/docs/how-to-guides/develop-a-flex-flow/class-based-flow.md
+++ b/docs/how-to-guides/develop-a-flex-flow/class-based-flow.md
@@ -239,6 +239,6 @@ There's several limitations on aggregation support:
 
 ## Next steps
 
-- [Supported types](./supported-types.md)
+- [Input output format](./input-output-format.md)
 - [Class based flex flow sample](https://github.com/microsoft/promptflow/blob/main/examples/flex-flows/chat-basic/README.md)
 - [Class based flex flow evaluation sample](https://github.com/microsoft/promptflow/blob/main/examples/flex-flows/eval-code-quality/README.md)
diff --git a/docs/how-to-guides/develop-a-flex-flow/function-based-flow.md b/docs/how-to-guides/develop-a-flex-flow/function-based-flow.md
index 87f0351f327..46307d0dbb7 100644
--- a/docs/how-to-guides/develop-a-flex-flow/function-based-flow.md
+++ b/docs/how-to-guides/develop-a-flex-flow/function-based-flow.md
@@ -4,7 +4,7 @@
 This is an experimental feature, and may change at any time. Learn [more](../faq.md#stable-vs-experimental).
 :::
 
-User can directly use a function(see [supported types](./supported-types.md) for typing support) as flex flow's entry.
+User can directly use a function (see [supported types](./input-output-format.md#supported-types) for typing support) as flex flow's entry.
 
 ## Authoring
 
@@ -93,10 +93,10 @@ pf flow serve --source "./flow.flex.yaml"  --port 8088 --host localhost
 
 ## Build & deploy
 
-Build & deploy a flex flow is supported like [DAG flow](../deploy-a-flow/index.md).
+Build & deploy a flex flow is supported, see [Deploy a flow](../deploy-a-flow/index.md).
 
 ## Next steps
 
 - [Class based flex flow](./class-based-flow.md)
-- [Supported types](./supported-types.md)
+- [Input output format](./input-output-format.md)
 - [Function based flex flow sample](https://github.com/microsoft/promptflow/blob/main/examples/flex-flows/basic/README.md)
diff --git a/docs/how-to-guides/develop-a-flex-flow/index.md b/docs/how-to-guides/develop-a-flex-flow/index.md
index 812ba7d659e..08ca1920893 100644
--- a/docs/how-to-guides/develop-a-flex-flow/index.md
+++ b/docs/how-to-guides/develop-a-flex-flow/index.md
@@ -4,26 +4,23 @@
 This is an experimental feature, and may change at any time. Learn [more](../faq.md#stable-vs-experimental).
 :::
 
-Flex flow is short cut for flexible flow. Which means it works for most scenarios with little adjustment.
+You can create LLM apps using a Python function or class as the entry point, which encapsulating your app logic. You can directly test or run these entries with pure code experience. 
 
-We provide guides on how to develop a flow by writing a flow yaml from scratch in this section.
+In PromptFlow, these functions or classes are referred to as `flex flow`. 
 
-Flex flow provides a new way to deploy your LLM app in prompt flow.
-Which has the following benifits:
+Alternatively, you can define a `flow.flex.yaml` that points to these entries (`entry:function_name` or `entry:ClassName`). This enables testing, running, or viewing traces via the [Promptflow VS Code Extension](https://marketplace.visualstudio.com/items?itemName=prompt-flow.prompt-flow).
 
-- Quick start (playground experience). Users can quickly test with prompt + python code with UI visualize experience. For example, user don't necessarily have to create YAML to run flex flow. See [batch run without YAML](./function-based-flow.md#batch-run-without-yaml) for more information.
-- More advanced orchestration. Users can write complex flow with Python built-in control operators (if-else, foreach) or other 3rd party / open-source library. 
-- Easy onboard from other platforms: other platforms like langchain and sematic kernel already have code first flow authoring experience. We can onboard those customers with a few code changes.
+Our [examples](https://github.com/microsoft/promptflow/tree/main/examples/flex-flows) should give you a good idea on how to write `flex flows`.
 
-## Stream
+Note: 
+- The term *Flex* is a shorthand for *flexible*, indicating its adaptability to most scenarios with minimal adjustments.
+- PromptFlow also supports the development of a `dag flow`. learn more on comparasion of these two [flow concepts](../../concepts/concept-flows.md).
 
-Stream is supported in flex flow.
-Reference this [sample](https://microsoft.github.io/promptflow/tutorials/stream-flex-flow.html) for details.
 
 ```{toctree}
 :maxdepth: 1
 
 function-based-flow
 class-based-flow
-supported-types
+input-output-format
 ```
diff --git a/docs/how-to-guides/develop-a-flex-flow/supported-types.md b/docs/how-to-guides/develop-a-flex-flow/input-output-format.md
similarity index 83%
rename from docs/how-to-guides/develop-a-flex-flow/supported-types.md
rename to docs/how-to-guides/develop-a-flex-flow/input-output-format.md
index f25acd642d0..f37a2b45dc5 100644
--- a/docs/how-to-guides/develop-a-flex-flow/supported-types.md
+++ b/docs/how-to-guides/develop-a-flex-flow/input-output-format.md
@@ -1,4 +1,6 @@
-# Supported types
+# Input output format
+
+## Supported types
 
 :::{admonition} Experimental feature
 This is an experimental feature, and may change at any time. Learn [more](../faq.md#stable-vs-experimental).
@@ -30,3 +32,10 @@ def my_flow(my_own_obj: MyOwnClass):
 ```
 
 Sample validation error: "The input 'my_own_obj' is of a complex python type. Please use a dict instead."
+
+
+
+## Stream
+
+Stream is supported in flex flow.
+Reference this [sample](https://microsoft.github.io/promptflow/tutorials/stream-flex-flow.html) for details.
\ No newline at end of file
diff --git a/docs/how-to-guides/develop-a-flow/index.md b/docs/how-to-guides/develop-a-flow/index.md
index eb23ee252b8..04484a9ed5f 100644
--- a/docs/how-to-guides/develop-a-flow/index.md
+++ b/docs/how-to-guides/develop-a-flow/index.md
@@ -1,5 +1,17 @@
-# Develop a flow
-We provide guides on how to develop a flow by writing a flow yaml from scratch in this section.
+# Develop a dag flow
+
+LLM apps can be defined as Directed Acyclic Graphs (DAGs) of function calls. These DAGs are flows in prompt flow.
+
+A `DAG flow` in prompt flow is a DAG of functions (we call them [tools](../../concepts//concept-tools.md)). These functions/tools connected via input/output dependencies and executed based on the topology by prompt flow executor.
+
+A flow is represented as a YAML file and can be visualized with our [Prompt flow for VS Code extension](https://marketplace.visualstudio.com/items?itemName=prompt-flow.prompt-flow). Here is an example `flow.dag.yaml`:
+
+![flow_dag](../../media/how-to-guides/quick-start/flow_dag.png)
+
+Please refer to our [examples](https://github.com/microsoft/promptflow/tree/main/examples/flows) and guides in this section to learn how to write a `DAG flow`. 
+
+Note: 
+- promptflow also support user develop a `flex flow`. learn more on comparasion of these two [flow concepts](../../concepts/concept-flows.md).
 
 ```{toctree}
 :maxdepth: 1
diff --git a/docs/how-to-guides/index.md b/docs/how-to-guides/index.md
index 2ef3019f381..f66e4267238 100644
--- a/docs/how-to-guides/index.md
+++ b/docs/how-to-guides/index.md
@@ -11,6 +11,7 @@ tracing/index
 ```{toctree}
 :caption: Flow
 :maxdepth: 1
+develop-a-flex-flow/index
 develop-a-flow/index
 execute-flow-as-a-function
 chat-with-a-flow/index