Update overview.md

Author: cocoindex-dev

docs/docs/getting_started/overview.md

@@ -5,20 +5,15 @@ slug: /
 
 # Welcome to CocoIndex
 
-CocoIndex is a ultra performant real-time data transformation framework for AI, with incremental processing. 
+CocoIndex is an ultra-performant real-time data transformation framework for AI, with incremental processing. 
 
 As a data framework, CocoIndex takes it to the next level on data freshness. **Incremental processing** is one of the core values provided by CocoIndex.
 
-<p align="center">
-    <img src="https://github.com/user-attachments/assets/f4eb29b3-84ee-4fa0-a1e2-80eedeeabde6" alt="Incremental Processing" width="700" />
-</p>
-
-
 ## Programming Model
 CocoIndex follows the idea of [Dataflow programming](https://en.wikipedia.org/wiki/Dataflow_programming) model. Each transformation creates a new field solely based on input fields, without hidden states and value mutation. All data before/after each transformation is observable, with lineage out of the box.
 
 The gist of an example data transformation:
-```
+```python
 # import
 data['content'] = flow_builder.add_source(...) 
 
@@ -34,13 +29,6 @@ collector.collect(...)
 collector.export(...)
 ```
 
-
-An example dataflow diagram:
-<p align="center">
-    <img width="700" alt="DataFlow" src="https://github.com/user-attachments/assets/22069379-99b1-478b-a131-15e2a9539d35" />
-</p>
-
-
 Get Started:
 - [Quick Start](https://cocoindex.io/docs/getting_started/quickstart)