For both C# and F#, the version of .NET indicates the version of the build tooling (msbuild, compilers, nuget packages, etc...) that will be used to build the c

For both C# and F#, the version of .NET indicates the version of the build tooling (msbuild, compilers, nuget packages, etc...) that will be used to build the code whenever you invoke `dotnet build`. That means, for example, that the F# team _could_ have shipped a language change between versions 8 and 9, but if they didn't then at least they could have shipped a compiler change or an msbuild change that required .NET 9 for whatever reason. For developers, usually you can just update your code to the latest available runtime version unless you have to wait for your deployment environment to have the latest .NET version installed. Nowadays that's not necessary due to MSBuild changes to create self-contained deployments, but something to know.