Skyrim:Light Armor

Light Armor is the skill governing your ability to fight and move in light armor. Each skill point increases your armor rating from Light Armor by 0.4% (1.5% for NPCs). The Light Armor skill tree has a total of 6 perks, requiring a total of 10 perk points to fill.

In-game Description: Those trained to use Light Armor make more effective use of Hide, Leather, Elven, Scale and Glass armors.     

Additional types of light armor that are forgeable: Imperial light armor, chitin armor , dragonscale, and Stalhrim light armor . There are also a few types of generic, unforgeable, light armor: fur armor, Blackguard's armor , Dawnguard armor , Forsworn armor, guard armor, Morag Tong armor , Skaal armor , Stormcloak armor, and vampire armor . Also, the artifacts Morokei, Volsung, Krosis, Wooden Mask, and Savior's Hide are classified as light armor.  Light shields, including the artifact called the Dawnguard Rune Shield , are not light armor in any meaningful sense - neither this skill's ranks nor perks interact with them.

Skill Perks
 
 
 


 

Comparison to Heavy Armor
Advantages:
Lighter weight and less movement penalty.
Less noisy, making sneaking easier.
The lighter weight allows for the carrying of multiple suits of armor, each fine-tuned for specific enemies and situations, without drastically taking up encumbrance (6 full sets of elven armor weigh slightly more than 1 full set of steel armor).
Once you reach the armor cap, light armor is arguably a better choice due to its lighter weight and less perk investments needed to unlock the more impactful perks.
The Unhindered perk (worn light armor is weightless) is available 20 levels earlier than Heavy Armor's Conditioning, and doesn't require taking two highly situational perks to unlock. However, due to the lower weight of light armors, it is also less powerful.
Consumes less stamina when sprinting.
Stamina recovers faster with the Wind Walker perk, which is very beneficial for dps focused characters.
Can be faster than the enemy, allowing you to run away from a battle or pursue a fleeing enemy for longer.
Deft Movement has a 1-in-10 chance to completely negate melee damage, which can make the difference in difficult fights at higher levels and/or difficulty settings, and makes light armor the most protective option at maximum armor rating.

Disadvantages:
Less protective in the early game, which in certain situations can be a fatal flaw. 
This can be exacerbated if you wear heavy armor early on and use the Warrior Stone to increase your One-handed or Two-handed skills, as Light Armor is not affected. You can use the Thief Stone to level your Light Armor and Archery at the same time, or you can find and use the Lover Stone to increase all skills at a slightly lesser rate.
Unintuitively, Light Armor's agility, speed, and lower protective value can lead to slower skill progression. Light Armor players tend to take less hits, which means less XP is acquired. Player damage, however, will continue to improve similarly to that of a heavy armor player, meaning enemies will die faster, further reducing damage taken and total skill experience. This can trigger a domino effect where players have too little durability to take damage, preventing them from gaining further XP, and stalemating their skill progression.
It can be harder to reach the armor cap with light armor. While a Heavy Armor user can reach it relatively easily with a combination of perks and smithing, light armor will require a more substantial investment into either enchanting or the smithing tree to achieve the same results. 
For comparison, a Heavy Armor player with Daedric armor can reach the armor cap with a fortified skill level of 148, while a Light Armor player requires a much more substantial fortified skill level of 297. These requirements are substantially lower after smithing is taken into account, but even so, achieving the armor cap with light armor will remain significantly more difficult.
Unarmed attacks are less powerful without Fists of Steel, though heavy investment in Fortify Unarmed enchantments can still make it a viable choice, albeit never as powerful as an equivalent Heavy Armor alternative.
Light armor lacks the Tower of Strength perk or an equivalent, meaning players will be staggered more easily, and will be ragdolled more frequently by Draugr's Unrelenting Force shout.

Skill Increases
Character Creation
The following races have an initial skill bonus to Light Armor:
+5 bonus: Argonian, Bosmer, Dunmer, Nord

Trainers
Scouts-Many-Marshes in Windhelm (Common)
Grelka in Riften (Expert)
Nazir in Dark Brotherhood Sanctuary, west of Falkreath or north of Dawnstar (Master)

Skill Books
Ice and Chitin
''Jornibret's Last Dance
Rislav The Righteous
The Rear Guard
The Refugees''

Free Skill Boosts
+1 Light Armor reward (as well as +1 Lockpicking) from Shahvee (Windhelm) for completing the quest Find Shahvee's Amulet of Zenithar inside  .
+1 Light Armor reward from Annekke Crag-Jumper for completing the quest Kill the Bandit Leader inside