The history of the naming of Microsoft’s .Net framework can sometimes be confusing.  

In 2016, Microsoft released a complete rebuild of the ASP.NET framework, which they called ASP.NET Core.  

Since 2020, they removed the “Core” part, so it’s now just called ASP.NET - the same as the old one.  

Umbraco 9 and above all run on the ‘new’ ASP.NET. Which means if you’re on Umbraco 8 or lower, it makes the upgrade to 9 or higher more complex.  

But, for that labour you get simpler development, much better performance, caching and optimization, and a much more web page-centric programming model.

To read up on the differences and capabilities, check out Umbraco’s great guide on what it means for the Umbraco CMS.

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