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 This is a study practice repository following [Essential ASP.NET Web Forms Development: Full Stack Programming with C#, SQL, Ajax, and JavaScript](https://learning.oreilly.com/library/view/essential-aspnet-web/9781484257845/)
 
+Markdown files within notes are majorly concept summary, practice will be executed within `/src` folder.
+
 Note: `.gitignore` file is generated by Gitea/GitHub.
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 ## 1.1 Introduction
 
+Overview of this chapter:
+* Client-server model.
+* .NET Framework
+* ASP.NET and C# Programming
+* Visual Studio
+* (Practice) How to start a new ASP.NET Web Application project
+
+## 1.2 Client-Server Model
+
+Client-Server Model distributes processing btw:
+* **server**: provider of resources/services
+  * e.g. of Web server app: *Internet Information Service (IIS)*, *Apache HTTP Server*, *Oracle iPlanet Web Server*
+* **client**: users of resources
+  * e.g. of Web client app: *Microsoft Internet Explorer*, *Google Chrome*.
+
+### Web Page: Static or Dynamic
+
+* Static web page: do not change for all requests.
+  * Before HTML5, `.html/.htm` files are static web pages.
+* Dynamic web page: 
+  * 
+
 ![Processing cycle of a static Web page](imgs/493603_1_En_1_Fig2_HTML.jpg)
+Processing cycle of a static Web page:
+1. Client requests a Web page from a Web server via *HTTP request*. content of request: 
+   1. Web page
+   2. IP of server & client
+2. After server received HTTP request, it 
+   1. locates desired web page file. 
+   2. Then attach HTML file to HTTP response.
+   3. send back to client
 
 ![Processing cycle of a dynamic Web page](imgs/493603_1_En_1_Fig3_HTML.jpg)
+Processing cycle of a dynamic Web page:
+1. Client requests a Web page from a server via an HTTP request. content of request:
+   1. name of dynamci Web page (e.g. `Display_Products.aspx`)
+   2. state of Web page controls (e.g. name in text box)
+2. After server received HTTP request
+   1. Check file exentention is `.aspx`, then pass processing control to the business logic of the server app (i.e. ASP.NET & C# code)
+   2. If business logic requies service from db (e.g. reading, inserting), the app server pass processing control and related args to db server.
+   3. After db server finish execution, it pass control back to app server
+   4. App server pass data/response back to web server
+   5. Web server formats HTML based on app server's work
+   6. Web server attach HTML to HTTP response
+   7. Web server sends response back to client
 
-![Organization of the .NET Framework](imgs/493603_1_En_1_Fig4_HTML.jpg)
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+This is a full backend service processing cycle
+
+## 1.3 .NET Framework
+
+* **.NET Framewok** = Windows-based software dev and execution framework
+* It consists of 
+  * **Framework Class Library (FCL)**: a large library of classes to create Windows desktop app, or Web app using VB, VC++, VC#, etc.
+  * **Common Language Runtime (CLR)**: environment where all .NET app executed. (Execution logic shown below)
+
+![Organization of the .NET Framework](imgs/493603_1_En_1_Fig4_HTML.jpg)
+
+## 1.4 OOP
+
+A class can contain *properties* & *methods* and can handle *events*.
+* **event** = end-user actions or other things that occur in time.
+* properties, methods, events are all **members** of the class
+
+### 1.4.1 Class and Objects
+
+2 types of classes in .NET Framework:
+* **non-static class**: contain non-static members that we can use, ONLY after we initialize an object from it.
+* **static class**: contain static members that can be directly utilized w/o initialization
+
+Class diagram (e.g. shown below, used to describe class in the book) include:
+* name of class
+* **namespace** of the class resides in: contain classes that provide specific functionality or specialized tpe
+* selected **properties**, **methods**, **events**
+* **event handler methods** are omitted in diagram in this book
+  * event handler methods = handler methods that raised by **event**; begin with "On", end with event name.
+
+### 1.4.2 Properties
+
+Properties:
+* = data of class
+* can be read from (via `get` method) and written to (via `set` method)
+
+### 1.4.3 Methods
+
+Omitted
+
+### 1.4.4 Events
+
+Events are things that happened
+* Raised by user action or sth in future.
+* When event is raised, methods are invoked to handle it.
+  * e.g. .NET Page class raises a **Load** event every time client reload web page.
+* Events can be static or non-static for different class.
+
+#### 1.4.5 Encapsulation
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