Microsoft Visual StudioVisual Studio.NET is the umbrella that represents the key pieces of the .NET platform delivered from Microsoft, including the .NET Framework, the recently announced .NET Core, and a shared common layer of packages, compilers and runtime. Read this .NET blog post about the evolution of the platform and the different pieces that make .NET 2015.
The price is good.
There's a community edition that is absolutely free to use. It's pretty good.