> For the complete documentation index, see [llms.txt](https://programmingblockchain.gitbook.io/programmingblockchain/llms.txt). Markdown versions of documentation pages are available by appending `.md` to page URLs; this page is available as [Markdown](https://programmingblockchain.gitbook.io/programmingblockchain/introduction/why_c.md).

# Why C#?

The .NET framework is popular in corporate environments. We also believe this is the perfect tool for startups and hobbyists.

* You can create portable code that functions across iOS, Android, Windows tablets/phones, desktops, servers and embedded devices, for free.
* Everything from the compiler to the core runtime is open source.
* The BizSpark program allows any startup to get all Microsoft tools, including $150/month of Azure service, for free.
* Visual Studio Community 2015 is a professional grade IDE that you can use freely as a hobbyist.
* C# is closely related to Java and C++. As such, it can be easily read by a big base of developers.
* Nicolas Dorier, one of the authors of this book, created the most popular Bitcoin Framework for .NET, called [NBitcoin](https://github.com/MetacoSA/NBitcoin).
* Every person I met who learned about C# will tell you it is the best language out there, even if it is not the one they are using at the moment.
* Recent Benchmark place .net Core C# performance way ahead of Java in almost every area. See for yourself [C# vs Java Benchmark](https://benchmarksgame-team.pages.debian.net/benchmarksgame/faster/csharp.html)

The authors of this book have over 15 years combined experience with C#. It is our go-to language for any project for fun or profit.

> **Fact:** We have not been paid by Microsoft. It’s not too late to change that.


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