Interface Rules

1) All method declarations are public within an interface. This is the default access modifier, which means you can omit the modifier in the declaration. As a matter of fact, if you code a modifier like protected, private, or even public, you will get a compiler error.
2)
An interface cannot contain data declarations. However, you can declare properties:int amountOfFood
{
get;
set;
}
3)
An interface can inherit from another interface. You may wish to add more functionality to the interface and keep the original less-specific interface as it is
interface ISnakeFeedable: IFeedable
{
void FeedSnake();
}