This is the project where we see the different sensors such as temperature sensor , gas sensor and ldr (light dependent resistor) these are put to gather and made necessary code and conections on aurdino  to bring the output 

The tools required are the 

aurdino , temperature sensor (dht11) , gas sensor , led and ldr 

make the appropriate connections as per the circuit diagram 

send the code to aurdino from the aurdino software

 

its so simple to make and its of effordable cost 

 

NOTE :- we need to download the library of dht11 sensor to run the code