.NET 5 introduces numerous enhancements including Web API improvements, Blazor WebAssembly, C# 9.0 features, and advancements in machine learning with ML.NET, all under a unified 'One .NET' vision. The framework focuses on cloud-native investments, cross-platform capabilities, and improved desktop applications. However, certain features like ASP.NET WebForms and Windows Workflow Foundation have not been carried over to .NET 5.