Sunwuko set - The caster build of the class. It only buffs Wave of Light, Lashing Tail Kick and Tempest Rush. It used to be best played as a ranged class with Wave of Light but the recent patch brought new power to Tempest Rush. SWK set has the highest set bonus amongst all of the monk sets.
Raiment of the Storms - The generator / Dashing Strike set. The set only buffs Dashing Strike after using a generator and buffs generators after using Dashing Strike. The set has a LOT of damage but it is fairly squishy and best used by high paragon players who can dump extra paragon into Vitality so they can survive.
Uliana’s Stratagem - The Exploding Palm set. It is a mainly melee set that relies on using Seven Sided Strike to detonate Exploding Palm and spreading EP via the Gungdo Gear bracers. It is an extremely fun build, imho, but it Is not as powerful as the other sets available. The build also suffers from pigeonholing since there is only 1 viable setup and skill selection.
Inna’s Mantra - The pet set. Inna’s is a universal set that buffs every ability while giving you a personal army of Mystic Allies to tank damage for you and help dps targets down. Since it buffs everything, it can be played as any setup but Inna WoL is the most damage the build is capable of.
Patterns of Justice - The Sweeping Wind / Tempest Rush set. This is the new set for monks and it requires both SW and TR to be active in order for it to buff everything that you do. It has VERY fast movement speed and with the change to TR items in the recent patch, has a lot of dps, but not as much as Sunwuko.
Legacy of Dreams / Legacy of Nightmares - The no set builds. LoD and LoN rely on either the LoD legendary gem or the LoN ring set, both are the same set bonus when fully geared up but LoD has a slight edge since you get more gear choices with 2 open ring slots. Both of these builds affect everything so they are versatile but typically played as a WoL build since WoL has the most sources of bonus damage amongst monk gear and has a HUGE area of effect.