Some inherent abilities added to types (including current ones), nothing earth-shattering just little quirks.
Normal - Takes 20% less damage from Normal attacks, healing moves heal 20% extra
Fire - Immune to Burn, power increased by 50% in sun, decreased by 50% in rain
Water - Damage from poison status reduced by 50%, power increased by 50% in rain, decreased by 50% in sun
Electric - When an Electric pokemon uses an Electric move it recovers health equivalent to Shell Bell
Grass - Immune to Leech Seed, recovers 1/16th health per turn in sun
Ice - Immune to Freeze, Defense increased by 50% in Hail
Fighting - Sleep inducing moves have -20% accuracy against Fighting Pokemon
Poison - Immune to Poisoning, if opponent is poisoned, Poison pokemon recover 1/16th health a turn
Ground - Immune to sandstorm, immune to hail
Flying - Speed increased by 20% when no weather is in play
Psychic - When a Psychic pokemon uses an Psychic move it recovers health equivilent to Shell Bell
Bug - Contact moves have an additional 5% chance to flinch when used by Bugs
Rock - Immune to Sandstorm, 50% extra defense in Sandstorm
Ghost - Physical moves have 5% less accuracy against ghosts
Dragon - Dragons do 10% extra damage when at full health, take 1/16 damage in Hail (second typing can change it to 1/8 or 1/32)
Dark - Attacking moves have +5% accuracy when used by a dark type
Steel - Immune to Sandstorm, Steel types take 10% less damage from physical moves
Fairy - When confused, simply loses a turn rather than hitting itself