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+# Section 1. What is C#?
+
+## The history of C#
+
+**Microsoft C#**
+* Orignal name: "C-like Object Oriented Language"
+* Announsed at July 2000 Microsoft Professional Developers Conference along with the .NET Framework
+* Mono is the open-source competitor to C#
+
+**C#'s Original Specification Document**
+* Intended to be a simple, modern, general-purpose, object-oriented language
+* Support software engineering principles:
+  * strong type checking
+  * array bounds checking
+  * detection of attempts to use uninitialized variables
+  * auto garbage collection
+* Suitable for deployment in distributed environments
+* High portability (Software can be compiled and linked from source code for different operating systems and processors)
+* Suitable for writing applications for both **hosted** (large OS) and **embedded** systems (small functions)
+* C# has low memory and processing power consumption, but not good as C or assembly
+
+## C#, the .NET Framework and runtime
+
+**.NET Framework**
+* a software framework
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