Update _docs/concepts/build_system/index.md

Co-authored-by: FranFin <58737168+FranFin@users.noreply.github.com>

Author: pablogs9

_docs/concepts/build_system/index.md

@@ -45,7 +45,7 @@ ros2 run micro_ros_setup create_firmware_ws.sh [RTOS] [HARDWARE BOARD]
 
 It is possible to obtain a list of the supported hardware by running the command without any argument. By doing so, it is possible to see that along with the RTOSes and hardware supported by micro-ROS this build system also provides with three extra options:
 - By using `zephyr` as RTOS and `host` as hardware name, it is possible to obtain a Zephyr RTOS image with your micro-ROS app that runs in your host computer. 
-- By using just `host` as RTOS, micro-ROS will build a set of [micro-ROS demo applications](https://github.com/micro-ROS/micro-ROS-demos) natively in your host machine. This applications behaves just like a micro-ROS app (using the same layers and middleware) but allows the user to debug and test the applications.
+- By using just `host` as RTOS, micro-ROS will build a set of [micro-ROS demo applications](https://github.com/micro-ROS/micro-ROS-demos) natively in your host machine. These applications behave just like micro-ROS apps (using the same abstraction layers and middleware implementation) and allow the user to debug and test the applications on a PC.
 - By using `generate_lib` as RTOS it is possible to configure the build system for generating static libraries (`.a`) and a set of headers (`include`) that can be linked in any other external tool. This option requires a valid CMake toolchain.
 
 Once the build system has created the new firmware project, it is possible to configure it using: