Serial communication between two Arduino

I am working on home automation project for this I am using multiple ultrasonic sensors,I am thinking of taking all the sensors data in one Arduino and control all the relay from the other Arduino,How can I do that?

ever heard of I2C? you can flawlessly send data back and forth between two arduinos or more over I2C (wired) , or wirelessly over bluetooth ( hc 12, hc 05 not hc 06 )

major drawback of I2C is that, distance is of great concern, signals somehow get impaired in long runs

I am working on home automation project for this I am using multiple ultrasonic sensors,I am thinking of taking all the sensors data in one Arduino and control all the relay from the other Arduino,How can I do that?

In most cases it's not necessary to split that functionality up into two Arduinos. Only in rare and rather complex scenarios this split-up makes sense. Tell use more details about your project, maybe we can help to keep the complexity in an acceptable range.

Himanshu_rai:
,I am thinking of taking all the sensors data in one Arduino and control all the relay from the other Arduino,

Do you really need to do this?
What sort of Arduinos?
How many sensors?
How many relays?