Ok so I am familiar with developing Form and Console applications on Windows using Visual Studio .Net with C#, but where do I start when it comes to Linux distro's like Ubuntu, is there an equivalent?

How would one go about matching what they can do in a Windows environment with .Net and C# in a Linux environment without .Net coding in something like Java or C/C++?

I am aware of Eclipse, does eclipse have a form designer or do you have to code the design of any Gnome/Unity forms manually? Can I use eclipse to write the Linux equivalent of a console application, that you just double click on to run?

I also know about Mono, but the idea is that I want to learn how to develop software without using anything in the Microsoft stack and am not sure where to start.

What is the standard language/framework used to develop these types of applications on Linux?

As I become more proficient with Visual Studio, C# and .Net, it has struck me that without these Microsoft tools, I am nothing. I am only capable of developing for the Microsoft OS and this scares me. This isn't some anti Microsoft thing, Microsoft makes some incredible Software/Hardware/Operating Systems/IDE's, but it is generally a bad idea to put all of your eggs in one basket so if I want to learn how to develop Terminal and Gnome/Unity form applications where in the world do I start?

I have used Linux on and off for years, but Windows has been my primary OS. However I have watched Linux get better and better and as much as I love Windows 7, I am dubious about Windows 8 (I for one will sorely miss my start menu)! Obviously MS aren't going anywhere anytime soon and I could spend the the next couple of decades developing for .Net without any issues but just because you can get away with something doesn't always mean it's a good idea.

Thanks