What is the best pokemon type (ex: fire, water)

Ok I measured these using the following calculation.

Super effective moves that does 2X damage = + or - 2.
Super effective that does 4X damage is + or - 4
Immune is + or - 4
Not very effective /2 also + or - 2
Not very effective /4 is + or - 4.
Finally if it's a dual type and the pokemon has both moves available for attack than it gets a +10

Note: it originally is split into two categories offensive and defensive and than added together. That is why any type of move could be positive or negative.

(I hope that wasn't too confusing)

steel is the strongest type for single type ,however,the overall best are steel and water, steel and ground, steel and ghost, and lastly steel and dragon. And they are all equally strong.

Examples:
Steel and Water = Empolean
Steel and Fire = Heatran
Steel and Ground = Steelix
Steel and Ghost = None so far
Steel and Dragon = Dialga

I hope this helped and if you're interested in using this calculator for yourself feel free at elite-four-champion.com