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Distinguished Engineer who has created other products and languages, including Borland Turbo C++ and Borland Delphi. With C#, he focused on taking what was right about existing languages and adding improvements to make something better.

C# is a powerful and flexible programming language. Like all programming languages, it can be used to create a variety of applications. Your potential with C# is limited only by your imagination. The language does not place constraints on what you can do. C# has already been used for projects as diverse as dynamic Web sites, development tools, and even compilers.

C# was created as an object-oriented programming (OOP) language. Other programming languages include object-oriented features, but very few are fully object-oriented. Later in today’s lesson you will understand how C# compares to some of these other programming languages. You’ll also learn what types of applications can be created. On Day 2, “Understanding C# Programming,” you will learn what it means to use an object-orient- ed language.

Why C#?

Many people believed that there was no need for a new programming language. Java, C++, Perl, Microsoft Visual Basic, and other existing languages were believed to offer all the functionality needed.

C# is a language derived from C and C++, but it was created from the ground up. Microsoft started with what worked in C and C++ and included new features that would make these languages easier to use. Many of these features are very similar to what can be found in Java. Ultimately, Microsoft had a number of objectives when building the language. These objectives can be summarized in the claims Microsoft makes about C#:

•C# is simple.

•C# is modern.

•C# is object-oriented.

In addition to Microsoft’s reasons, there are other reasons to use C#:

•C# is powerful and flexible.

•C# is a language of few words.

•C# is modular.

•C# will be popular.

C# Is Simple

C# removes some of the complexities and pitfalls of languages such as Java and C++, including the removal of macros, templates, multiple inheritance, and virtual base classes. These are all areas that cause either confusion or potential problems for C++ developers. If you are learning C# as your first language, rest assured—these are topics you won’t have to spend time learning!

C# is simple because it is based on C and C++. If you are familiar with C and C++—or even Java—you will find C# very familiar in many aspects. Statements, expressions, operators, and other functions are taken directly from C and C++, but improvements make the language simpler. Some of the improvements include eliminating redundancies. Other areas of improvement include additional syntax changes. For example, C++ has three operators for working with members: ::, ., and ->. Knowing when to use each of these three symbols can be very confusing in C++. In C#, these are all replaced with a single symbol—the “dot” operator. For newer programmers, this and many other features eliminate a lot of confusion.

C# Is Modern

What makes a modern language? Features such as exception handling, garbage collection, extensible data types, and code security are features that are expected in a modern language. C# contains all of these. If you are a new programmer, you might be asking what all these complicated-sounding features are. By the end of your twenty-one days, you will understand how they all apply to your C# programming!

an integral part of the language. If you are not familiar with the concepts of pointers, garbage collection, and type safety, don’t worry. These are all explained in later lessons.

C# Is Object-Oriented

The keys to an object-oriented language are encapsulation, inheritance, and polymorphism. C# supports all of these. Encapsulation is the placing of functionality

into a single package. Inheritance is a structured way of extending existing code and functionality into new programs and packages. Polymorphism is the capability of adapting to what needs to be done. Detailed explanations of each of these terms and a more detailed description of object orientation are provided in Day 2’s lesson. Additionally, these topics are covered in greater detail throughout this book.

C# Is Powerful and Flexible

As mentioned before, with C# you are limited only by your imagination. The language places no constraints on what can be done. C# can be used for projects as diverse as creating word processors, graphics, spreadsheets, and even compilers for other languages.

C# Is a Language of Few Words

C# is a language that uses a limited number of words. C# contains only a handful of terms, called keywords, which serve as the base on which the language’s func-

tionality is built. Table 1.1 lists the C# keywords. A majority of these keywords are used to describe information. You might think that a language with more keywords would be more powerful. This isn’t true. As you program with C#, you will find that it can be used to do any task.

TABLE 1.1 The C# Keywords

TABLE 1.1 continued

C# Is Modular

C# code can (and should) be written in chunks called classes, which contain routines called member methods. These classes and methods can be reused in other

applications or programs. By passing pieces of information to the classes and methods, you can create useful, reusable code.

C# Will Be Popular

C# is one of the newest programming languages. At the time this book was written, it was unknown as to what the popularity of C# would be, but it is a good bet that this will become a very popular language for a number of reasons. One of the key reasons is Microsoft and the promises of .NET.

Microsoft wants C# to be popular. Although a company cannot make a product be popular, it can help. Not long ago, Microsoft suffered the abysmal failure of the Microsoft Bob operating system. Although Microsoft wanted Bob to be popular, it failed.

C# stands a better chance of success than Microsoft Bob. I don’t know whether people at Microsoft actually used Bob in their daily jobs. C#, however, is being used by Microsoft. Many of its products have already had portions rewritten in C#. By using it, Microsoft helps validate the capabilities of C# to meet the needs of programmers.

Microsoft .NET is another reason why C# stands a chance to succeed. .NET is a change in the way the creation and implementation of applications is done. Although virtually