Edge-canceled eggs (abbreviated "ECE") is a planking technique performed by Yoshi that is performed by releasing from the edge, by pressing down or away from the edge, double jumping, and then throwing an egg. This must be done fast enough so that when done, the player does not land on the stage or too far above the edge. After the egg is thrown, the player can grab onto the edge, canceling all lag and renewing the edge invincibility frames. Players such as aMSa are notorious for doing this to stall, and being able to do this for extended periods of time.
Reverse edge-canceled eggs
Reverse edge-canceled eggs (abbreviated "RECE") is a technique similar to ECE. Reverse edge-canceled eggs are performed in generally the same way, but instead of launching the eggs towards the stage, the eggs are launched outwards. This is done by quickly turning around with the player's second jump. This is a more risky alternative because if missed, Yoshi will plummet to his death. This technique is not possible in Brawl, as Yoshi can no longer toss his eggs backwards.
Edge-cancelled eggs is a rather useful technique in the first three games, due to allowing Yoshi to easily camp, space, and play defensively while countering opponent approaches. The reverse edge-cancelled eggs technique is a pretty risky but useful edgeguarding tactic if one can perform it consistently, giving Yoshi strong ledge play.