Some of Unity's reference notes in C # programming

System
Contains the underlying classes and base classes used to define common values and reference data types, events and event handlers, interfaces, properties, and handling exceptions. Other classes provide services that support the following operations: Data type conversions, method parameter manipulation, mathematical calculations, remote and local program invocation, application environment management, and governance of managed and unmanaged applications.

System.Collections
Contains interfaces and classes that define collections of various objects, such as lists, queues, bit arrays, hash tables, and dictionaries.

System.Collections.Generic
Contains interfaces and classes that define generic collections, and generic collections allow users to create strongly typed collections that are better type-safe and performance-superior than non-generic strongly-typed collections.

System.ComponentModel
Provides classes for implementing run-time and design-time behavior for components and controls. This namespace includes the base classes and interfaces for the implementation of properties and type converters, data source bindings, and component authorization.

System.Data
Contains classes that make up most of the ADO structure. The ADO structure allows you to build components that can be used to effectively manage data from multiple data sources. In disconnected scenarios such as the Internet, ADO provides a number of tools that can request, update, and reconcile data in a multi-tiered system. The ADO structure can also be implemented in a client application, such as a Windows form, or an HTML page created by ASP.

System.Drawing
Provides access to the basic graphics features of GDI +. More advanced features are available in the System.Drawing.Drawing2D, System.Drawing.Imaging, and System.Drawing.Text namespaces.

System.Text
Contains classes that represent ASCII, Unicode, UTF-7, and UTF-8 character encodings, an abstract base class for converting between word converts sequential blocks and byte blocks, and helper classes that do not need to create intermediate instances of strings to manipulate and format string objects.

System.Windows.Forms
Contains classes for creating Windows-based applications that take advantage of the rich user interface features in the Microsoft Windows operating system.

Some of Unity's reference notes in C # programming