There are several types of armor characterized by the degree of protection & maneuverability it provides. Any character may wear any type of armor as long as the minimum requirements are met.
All armor has 3 attributes that determine its overall suitability: Hardness, Weight, Durability. Like most items, armor also has a Quality attribute that strongly influences the base value & useful life of the item.
Hardness is a measure of how much physical abuse the armor can take.
Weight is a measure of how much the armor will encumber a character while it is worn. Characters with a high strength are better suited for the heaviest armors whereas a more agile character will benefit from leather.
Durability is the measure of how much damage can be absorbed in a single attack. Damage exceeding this value reduces the characters health & may damage the armor.
Various types of damaging attacks are more or less effective against each armor type. Blunt, Slash & Pierce attacks typically occur in melee combat, but the rest can occur almost anywhere, be it at the behest of a hostile spellcaster or passing storm. Rot & Rust are a more subtle type of threat, as they do damage over time. Lack of maintenance for gear can lead to failure at critical moments.
The chart below shows how the various damage types affect armor. Studying the chart, we can see some interesting facts. Plate mail is clearly superior protection from melee attacks, however it is susceptible to electric & sonic attacks. Leather armor offers economical albeit modest protection from the most damage types. Lastly, we can note that piercing damage is the most difficult to defend against.