ASP.NET 5 is just ASP.NET vNext, ASP.NET formally called ASP.NET vNext.
ASP.NET 5 is a significant redesign of ASP.NET.
ASP.NET 5 is a new open-source and cross-platform framework for building modern cloud-based Web applications using .NET. We built it from the ground up to provide an optimized development framework for apps that are either deployed to the cloud or run on-premises…… You can develop and run your ASP.NET 5 applications cross-platform on Windows, Mac and Linux.
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