The edition of this text has been written to initiate the newcomer to Real Time Operating System, one of the fastest growing fields in the engineering world. The majority of the RTOS's (Real Time Operating System's) have restricted asset limitations for Wireless Sensor Platforms. Virtual memory performs a noteworthy part in remote sensor systems. Expand the measure of the virtual memory is a major issue for creating sensor network building design. Virtual memory is upheld by means of a compiler's support, so sensor stage is able to implement a code bigger than a physical code. Coverage Includes: 1. An overview of RTOS: Multithreading, Scheduling, Interfaces 2. RTOS Design Fundamentals 3. WSN Platform for RTOS 4. Real Time Implementation of WSN