Crowd Control (abbreviated to CC) is the term used to describe an ability or spell that temporarily reduces a unit's ability to fight. The term 'crowd control' comes from the ability to control the enemy team during fights, by either restricting their contribution or means to escape. In addition, the use of crowd control can aid in your own survivability: in the same way you can stop them from escaping, you can stop them from following. Crowd control does not make an enemy untargetable. In the case of Airborne effects, the target is considered to be on the ground for the purposes of skill shots and area of effect damage (such as Morgana's Tormented Soil).
Types of Crowd Control
The following are the current forms of crowd control that exist within League of Legends:
Airborne: A unit that is airborne is unable to control their movement, attack or cast abilities for the duration. The duration is also unaffected by crowd control reduction and cannot be removed by cleansing effects.
Knockback: A knockback causes the target to be made airborne in a direction away from the point of cast.The duration depends on how far the target travels, from 0.75 seconds ( Rammus's Powerball) to 1.5 ( Lulu's Wild Growth).
Knockup: A knockup causes the target to be made airborne on the spot. The duration depends on how high is the target thrown into the air, from 0.75 seconds ( Rammus's Powerball) to 1.5 ( Lulu's Wild Growth).
Pull/Fling: A pull effect causes the target to be made airborne in a direction toward the point of cast.
Blind: A unit that is blinded will miss their auto-attacks for the duration.
Entangle: A unit that is entangled is unable to control their movement or attack for the duration.
Forced Action: A unit that is under the effect of a forced action cannot control their own movement or attacks, and is unable to cast abilities.
Charm: A unit that is charmed will move toward the source for the duration.
Fear: A unit that is feared will walk in random directions with reduced movement speed for the duration.
Flee: Targeted unit will move away from the attacker. (Onslaught of Shadows (Ultimate) - Hecarim)
Taunt: A unit that is taunted will attempt to attack the source of the taunt for the duration.
Polymorph: A unit that is pacified cannot attack or cast abilities, and has reduced movement speed for the duration.
Silence: A unit that is silenced cannot cast abilities for the duration.
Slow: A unit that is slowed has reduced movement speed for the duration.
Snare: A unit that is snared is unable to control their movement for the duration.
Stun: A unit that is stunned is unable to control their movement, attack or cast abilities for the duration.
Suppression: A unit that is suppressed is unable to control their movement, attack, cast abilities or use spells (including Cleanse). The duration is also unaffected by crowd control reduction.
Categorization
Loss of Control Crowd control is often categorized into two categories depending on whether or not the effect removes total control of the player's character.
Hard CC — The following effects completely remove control of one's character:
Airborne
Forced Action
Stun
Suppression
Soft CC — The following only remove partial control of one's character:
Blind
Entangle
Polymorph
Silence
Slow
Snare
Disruption
As an alternative to the above, crowd control is sometimes categorized into two categories depending on whether or not the effect disrupts the channelling of an ability; abilities such as Karthus's Requiem and Katarina's Death Lotus.
Hard CC — The following effects disrupt the channelling of abilities:
Airborne
Forced Action
Polymorph
Silence
Stun
Suppression
Soft CC — The following effects do not disrupt the channelling of abilities:
Blind
Entangle
Slow
Snare
Modifiers
Abilities can also be categorized by what their effects inhibit.
Movement Modifiers — The following effects in some way inhibit movement:
Airborne
Entangle
Forced Action
Slow
Snare
Stun
Suppression
Action Modifiers — The following effects in some way inhibit the ability to attack or cast abilities:
Airborne
Blind
Entangle
Forced Action
Polymorph
Silence
Stun