Juggling is a type of combo that involves repeatedly hitting someone into the air without letting them recover or hit the ground. The name comes from the motion of the victim vaguely resembling the motion that objects make when juggled.
In video games, juggling originated with Mortal Kombat. In the fighting games that came before, air-born enemies were usually immune to attacks.
The most common way to juggle is by continuously using up tilts, but up aerials can also be used, especially for air juggling. This is an effective technique to damage opponents that have poor means of protecting themselves from below. Juggling becomes harder as damage increases since the opponent experiences greater knockback, allowing more opportunities for escape or retaliation.
A character's vulnerability to juggling depends on several factors. Size, weight, falling speed, gravity, and hitstun may all play a role in determining how successful juggling might be. Higher values of these attributes generally allow the opponent to be juggled longer while lower values generally makes escape or retaliation from juggling easier. This is not completely true in the air, however, because a lower gravity and falling speed means the victim spends more time in the air.
Certain characters can close off stocks through the use of juggling and recovery moves, such as Dolphin Slash and Boost Kick, by using aerial attacks to push them to the upper blast line and then using the move, knocking them above the blast line and KOing them.
General ways to escape juggling include effective DI and air dodging. Momentum cancelling/altering aerials and specials as well as stall-then-fall moves are also useful in aiding escape. Some moves have unique effects that allow players to escape, such as Kirby's Stone or Mewtwo's Teleport. Characters that have a counterattack have a special resistance to juggling, as continuous attacks are required to sustain the combo.