Keil® MDK stands out as the ultimate software development package for Arm®-based microcontrollers, encompassing all necessary elements for crafting, building, and troubleshooting embedded applications. The foundation of MDK-Core lies in µVision (exclusive to Windows), offering exceptional support for Cortex-M devices, especially with the introduction of the advanced Armv8-M architecture. Within MDK, users gain access to the Arm C/C++ Compiler, which is accompanied by an assembler, linker, and highly efficient run-time libraries designed for optimal code size and performance. Additionally, users can enhance MDK-Core at any moment by integrating Software Packs, allowing for seamless updates in device support and middleware that are independent of the toolchain. These packs consist of device support, CMSIS libraries, middleware, board support, code templates, and illustrative example projects. Furthermore, the integrated IPv4/IPv6 networking communication stack is augmented with Mbed™ TLS, facilitating secure online connections. This powerful tool is ideal for product evaluation, smaller projects, and educational purposes, although it does impose a restriction on code size to a maximum of 32 Kbytes, making it suitable for various embedded applications while still being resource-efficient.