Mono Framework

Mono is a cross-platform implementation of the pieces that make up the .Net framework, like the CLR, C#/VB.Net compilers, and the base class libraries. Currently, Mono supports just about everything available in .Net 2.0. There are a few notable exceptions, like Windows.Forms' DataGridView and ASP.Net's WebParts. There are also a couple of namespaces that don't really have a Linux equivalent like EnterpriseServices, System.Management, and System.Messaging.

The .NET Framework is Microsoft's platform for building applications that have visually stunning user experiences, seamless and secure communication, and the ability to model a range of business processes. And it is Only for Windows Platforms.

The major components of Mono include:

Code Execution Engine

Class Libraries

Base Class Library

.NET Compatibility Class Libraries

Mono specific class libraries:

Cross platform class libraries for both Mono and .NET (Gtk#, Mono.Cecil, Mono.CSharp, Text.Templating)

Unix-specific class libraries (POSIX, Filesystem in Userspace (FUSE), curses)

Platform-specific class libraries (bindings for: Mac, iOS, Android, MeeGo)

CLI Assemblies

CLI Metadata

Mono's Common Language Runtime

Compatible with the ECMA Common Language Infrastructure/.NET Common Language Runtime

Mono-specific enhancements:

Mono.SIMD support

Mono co-routines and continuations.

Mono-specific enhancements

Native interop services and COM interop

Security - Transparent Code Framework