Sensors play a very important role in Arduino and electronics projects.
They help the system detect changes in the environment and respond accordingly.

## What is a Sensor?
A sensor is an electronic device that detects physical changes such as
temperature, light, motion, gas, or distance and converts them into signals.

## Common Sensors Used in Arduino Projects

### Temperature Sensor
Temperature sensors are used to measure heat levels.
They are commonly used in weather stations and automation projects.

### Ultrasonic Sensor
Ultrasonic sensors measure distance using sound waves.
They are widely used in obstacle detection and robotics projects.

### IR Sensor
IR sensors are used to detect objects and motion.
They are commonly used in line-following robots.

### Gas Sensor
Gas sensors detect harmful gases and smoke.
They are used in safety and monitoring systems.

### LDR (Light Sensor)
LDR sensors detect light intensity.
They are used in automatic street light projects.

## Applications of Sensors
Sensors are used in:
- Arduino projects
- Robotics
- Home automation
- IoT systems
- Industrial monitoring

## Conclusion
Sensors make electronics projects smarter and more interactive.
Choosing the right sensor helps in building efficient and reliable projects.