Update introduction.ipynb (microsoft#1934)

* Update introduction.ipynb

* fix json

* word

website/docs/tutorial/introduction.ipynb

@@ -18,14 +18,18 @@
     "> _The whole is greater than the sum of its parts._<br/>\n",
     "> -**Aristotle**\n",
     "\n",
-    "While there are many definitions of agents, in AutoGen, an agent is an entity that reacts to its environment. This abstraction not only allows agents to model real-world and abstract entities, such as people and algorithms, but it also simplifies implementation of complex workflows as collaboration among agents.\n",
+    "While there are many definitions of agents, in AutoGen, an agent is an entity that can send messages, receive messages and generate reply using models, tools, human inputs or a mixture of them.\n",
+    "This abstraction not only allows agents to model real-world and abstract entities, such as people and algorithms, but it also simplifies implementation of complex workflows as collaboration among agents.\n",
     "\n",
-    "Further, AutoGen is extensible and composable: you can extend a simple agent with customizable components and create workflows that can combine these agents, resulting in implementations that are modular and easy to maintain.\n",
+    "Further, AutoGen is extensible and composable: you can extend a simple agent with customizable components and create workflows that can combine these agents and power a more sophisticated agent, resulting in implementations that are modular and easy to maintain.\n",
     "\n",
     "Most importantly, AutoGen is developed by a vibrant community of researchers\n",
     "and engineers. It incorporates the latest research in multi-agent systems\n",
-    "and has been used in many real-world applications, including math problem solvers,\n",
-    "supply chain optimization, data analysis, market research, and gaming."
+    "and has been used in many real-world applications, including agent platform,\n",
+    "advertising, AI employees, blog/article writing, blockchain, calculate burned areas by wildfires,\n",
+    "customer support, cybersecurity, data analytics, debate, education, finance, gaming, legal consultation,\n",
+    "research, robotics, sales/marketing, social simulation, software engineering,\n",
+    "software security, supply chain, t-shirt design, training data generation, Youtube service..."
    ]
   },
   {