How are Igloos WARM Inside Even Though It Made of SNOW?!

You are scouting a snowy landscape with a temperature way below the freezing temperature. Everywhere is thick snow and you cannot figure out how to keep yourself warm. Suddenly, you remember that the Inuit live in snow houses called igloos. These are simple houses made with ice stacked on each other.

How can living inside an ice house or igloo keep you warm? What is the science behind it? How does cold negate cold? Well, all these answers can be obtained when you know the actual scientific fact behind an igloo.