Capcom has announced the weapon classes for Monster Hunter World, there are three larger groups, Light, Heavy and Technical and then within each group there are breakdowns further.
Each weapon type has a different overall playstyle and characteristics which are showcased in the videos. Swords and blades can be useful in cutting damage and executing fast paced attacks, impact weapons like hammers can cause high damage and stun opponents whilst ranged weapons such as bowguns allow you to attack beasts from afar. If the hunt is too overwhelming, support style weapons can be very useful such as the hunting horn which plays melodies that provide buffs for the team.
To see the breakdown of all weapon groups, click here.