ASP.NET MVC5 and ASP.NET Core are both web application frameworks developed by Microsoft, but they have some fundamental differences in terms of architecture, features, and capabilities. ASP.NET MVC5 is based on the full .NET Framework, while ASP.NET Core is based on .NET Core. Therefore, learning ASP.NET MVC5 is not required before learning ASP.NET Core, but it could be helpful in some cases. However, if you are new to web development, you can start with ASP.NET Core directly to build cross-platform web applications.