i am making a project on GSM based automation system. I am confused over the realay working as i have never worked on it before. Can anyone suggest which relay can be the best for operation of my project and also how i can interpret it physically.

 

I'm not the sharpest tack inthe box so explain GSM, we've played with lots of relays, but it would help if we knew what it is used for.

 

well the project goes like there a gsm module connected to the microcontoller. when a specified text is received over the number in the GSm module, the microcontroller activates and based on the text it has received it actuates a specific home appliance as in a fan or a tube light. i am clear of the portion till actuation but i am unable to get the woking of the relay. the relay in the circuit is 12V 1C/O but i dont understand the mening nor how it shall help me work out.