an item named dragon fang improves dragon type moves
Dragon type moves are only super effective against Dragon type Pokemon.
Like Dragonite, Salamence is a Dragon and Flying type. It's only weaknessess are: Ice type moves Rock type moves Dragon type moves
Flygon is a dragon and ground type its weak against ice type moves and dragon type moves.
Dragon type Pokemon are weak against Ice, Dragon, and Fairy type moves.
Dragon Pokemon are weak to ice and dragon type moves, and resistant to electric, fire, grass, and water type moves (By resistant I mean that when those type moves hit a dragon Pokemon, they will only do half the damage that they normally would). (This answer only applies to pure dragon Pokemon. Extra types such as flying/dragon, will have more weaknesses and strengths.)
Flygon is a Dragon and Ground type pokemon. It's weaknesses are Ice type moves and Dragon type moves.
A Dark Dragon Pokemon takes double damage from Fighting, Ice, Bug and Dragon moves.
Dragon type moves are not very effective against Steel types. Dragon and Ice type moves are super effective against Dragon types.
Dragon, Ice and Fairy-type moves.
Ice, Fairy and Dragon-type moves.
Steel-type and Dragon-type moves are supper effective on dragon-type Pokemon :)
It Ups the power of dragon type moves