Micro electro mechanical systems, or MEMS, is a process technology used to create tiny integrated devices or systems that have both mechanical and electronic components. The functional elements of MEMS are miniaturized structures, sensors, actuators and microelectronics.Various materials used in micro machined based refreshable Braille cell and its properties and Designing of micro machined braille cell using MEMS design software are discussed in the first chapter.A description of how an ammonia mems sensor is designed using MEMS design software is explained in the second chapter.In the third chapter the design of capacitive micromachined ultrasonic transducer using MEMS design software.