Humidifier Question!

I am a FTM I'm due any day now and I just need a few things left to check off my baby list. I couldn't help but noticed that there's cool mist and warm mist humidifiers and I was wondering what's the difference of them and if you ladies could help me choose what would be best for me?
My house is really big and it gets really cold at night even my room as well ofcourse I will have a heater while my baby is co sleeping with me in my room but I'm wondering if a warm mist humidifier would be best?
Then when he's around 3months I will be moving Into my new home where summer time it gets very hot and humid... 
Someone PLEASE explain more about humidifiers since I have ZERO experience with them! THANK YOU❤