Sandeep Pawar gives us the gentle version:
At MS Build, Microsoft announced availability of Native Execution Engine in Fabric. The product team will have detailed documentation and technical details but I will attempt to provide an ELI5 version of what it means and how it works at a 30000 ft level.
Read on to learn what the Native Execution Engine is and why Microsoft would use it versus running everything in the Java Virtual Machine like other services in the broader Hadoop ecosystem have historically done (at least at the beginning, before they built their own native execution engines!).