Here are some common safety terms and what they mean:
CE rated: indicates the product has been tested by the manufacturer and meets EU safety protection requirements.
AAA rated: highest level of protection from impact and abrasion. Recommended for track racing where speeds are incredibly high. Includes both abrasion protection (thicker leather, Kevlar, Dyneema, etc.) and armor for impact reduction.
AA rated: middle level of protection from impact (armor) and abrasion (leather, Kevlar, Dyneema, etc.) Recommended for riding at regular speeds; the most common rating needed for the riding most people do on a daily basis.
A rated: lowest level of protection from impact and abrasion. Ideal for lower speed riding, like city riding. Slide time is lower than AAA and AA, but the garment still includes armor and an abrasion resistant material.
B rated: abrasion protection only; does not include impact protection.
C rated: impact protection only; does not include abrasion protection. Common in summer gear and off-roading gear.
Slide time: occasionally included in a garment's rating, it indicates how many seconds of sliding the gear can withstand.
Armor: Level 2 is stronger than Level 1. Each manufacturer makes theirs a little differently, though most are soft and flexible, but harden on impact to absorb the impact.
Kevlar: used as a liner underneath a non-protective material, or woven into other material to provide abrasion protection. Most garments will also have pockets for armor as well for impact protection.
Cordura and Dyneema: both materials that, in the products we stock, are single layer protection so no other liner or material is needed. Again, most of these garments will also have pockets for armor for impact protection.
Leather: thickness is usually around 1.1 - 1.3mm to provide proper abrasion protection. If thinner, leather can be lined with Kevlar or similar to provide added resistance. Often also has pockets for armor and most come with armor.