Hi Hardik
A gyroscope is a mechanical system which can stabilize a thing in a particular position or direction. A gyroscopic sensor measures the angular velocity. It can be used to control pitch, roll and yaw of a quadcopter or somethign similar which demands structural stabilization.
Here are some links that might help you:
1. "youtube.com/watch?v=cquvA_IpEsA"
2. "howstuffworks.com/gyroscope.htm"
3. "amazon.in/Gyroscope-Accelerometer-Sensor-Arduino-Official/dp/B00TQX1A3S?tag=googinhydr18418-21&tag=googinkenshoo-21&ascsubtag=fd931371-ed68-459d-9a8e-1835db29c236"