Most modern programming languages include some form of runtime that provides common services and access to the underlying operating systems and hardware. Examples of this range from a simple functional library, such as the ANSI C Runtime used by C and C++, to the rich object-oriented class libraries provided by the Java Runtime Environment.
Similar to the way that Java programs depend on the Java class libraries and virtual machine, C# programs depend on the services in the .NET Framework such as the base class libraries (BCL) and the Common Language Runtime (CLR).
For a high-level overview of the BCL, see Chapter 4.
This chapter addresses the most common tasks you need to perform when building C# programs. These topics generally fall into one of two categories: leveraging functionality included in the BCL and interacting with elements of the CLR.
Certain types in the BCL are ubiquitous, in that they are fundamental to the way the BCL and CLR work and provide common functionality used throughout the entire BCL.
This section identifies some of the most common of these types and
provides guidelines on their usage. The types mentioned in this
section all exist in the
System.Object class is the root of the class
hierarchy and serves as the base class for every other class. The
object type aliases
System.Object provides a handful of useful methods that are present on all objects, ...