# 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. --- # Agent Instructions: Querying This Documentation If you need additional information that is not directly available in this page, you can query the documentation dynamically by asking a question. Perform an HTTP GET request on the current page URL with the `ask` query parameter: ``` GET https://programmingblockchain.gitbook.io/programmingblockchain/introduction/why_c.md?ask= ``` The question should be specific, self-contained, and written in natural language. The response will contain a direct answer to the question and relevant excerpts and sources from the documentation. Use this mechanism when the answer is not explicitly present in the current page, you need clarification or additional context, or you want to retrieve related documentation sections.