Edgeguarding

Edgeguarding (also called edge-guarding) is the act of attempting to stop your opponent from successfully recovering. The opposite of edge-guarding is Guard breaking.

Different Edgeguards and their Guard Breaks
Interruption Guard: These guards involve the edgeguarder jumping slightly or completely off the stage to deal an aerial attack to a recovering opponent. This puts the opponent in a very tricky situation, forcing them to mix up their recovery options to guard break it; however, in cases where a character's recovery is linear, predictable, and unsafe, such as, they usually cannot deal with this type of pressure, making it extremely efficient against these types of characters. Projectile Guard: These guards involve spamming a projectile to push an opponent gradually off the stage. This type of guard is easily broken by recovering from below, but can be lethal against a character who has a below-average vertical recovery. For these characters, air dodging at the right time is vital, or they will get KO'ed.
 * Spike Guard: This guard is used by characters with a strong Meteor Smash, usually an aerial one (thus making it a sub-type of the interruption guard). The guarder attempts to hit with a meteor smash to KO opponents. It is a very successful type of guard as the guarded must air dodge, or he or she will be KO'ed.

Reflect Guard: This guard is used by characters who have a special move that can change the direction of a projectile/character. When someone tries to recover, this is used to change the opponent's direction away from the stage, forcing them to fall to their death. The best example of this guard is and him using his Cape.

Edgehogging
Another way players can edgeguard their opponents is to prevent their opponents from grabbing the edge by "hogging" the edge themselves. This is usually done after the player who is trying to recover has performed his/her recovery move and is attempting to grab the ledge. The guarded is generally in serious trouble. The only possible guard break is to attack the edgehogger after the invincibility frames have ceased.

Wall/Fence of pain
This is a guard in which the edgeguarder repeatedly attacks the guarded with a repeated amount of forward or back aerial attacks to knock him or her towards the blast line for a KO. It is best performed with, since her aerials don't give enemies the time to react out of them, but a "Fence of Pain" can be performed by , , and. Kirby's Fence of Pain can be done with his back aerial, Tails's can be done with his forward aerial, and Meta Knight's can be done with his neutral aerial.