I can't tell what's the difference between these two from the description. Looks like .NET is also able to run not only on Windows?
I then tried to download both .NET and .NET core, then I got:
dotnet-sdk-3.1.404-win-x64.exe for .NET Core SDK
dotnet-sdk-5.0.100-win-x64.exe for .NET SDK
This is weird again, why .NET Core SDK is just like an old version of .NET SDK?