One of the most important gameplay mechanics in is the typings and their impact on battles; making memorizing and mastering their weaknesses and resistances crucial. In total, there are 18 different types, making a type chart very useful for Trainers looking to find out every Pokémon weakness and resistance. Initially, there were only 15 Pokémon types, with Dark and Steel added in Generation 2, while Fairy was introduced in Generation 6. Though some types have been adjusted since Gen 1, many have kept much of their original properties over the years.
Both logic and science decide a type's weaknesses and resistances. For example, Fire is weak to Water, Ground, and Rock because those can put out a fire. In contrast, Fire is strong against Grass, Ice, Bug, and Steel because it is able to burn/melt those things. These rules have kept the games relatively balanced throughout the series, and while some Pokémon Type matchups don't make sense, the system has largely been successful.
Related: How To Remember Every Pokémon Type Weakness & Resistance
Double Damage
Half Damage
Zero Damage
Each type has at least one other it is weak against and a handful of others it can resist or is strong against. There are also immunities that certain types hold against each other, meaning attacks do no damage, whereas resisting the type halves the damage.
If a type is weak to another type, the weak type will take double the damage from the attacking type.
Dual-type Pokémon are only slightly more complicated to figure out when it comes to weaknesses and resistances. Whichever two types are combined will offset any weaknesses one may have if the other resists it.
However, if both types are weak to the same type, it will quadruple the damage the
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