Feats are actions performed by various characters that are used to show their power. In debates on-panel feats hold the greatest value since they're solid proof of character's abilities. There're different type of feats such as speed feats, durability feats, strength feats etc.
Some feats are easy to quantify, such as dodging a bullet from a normal gun would make character supersonic+, while feats like dodging a blast from unknown weapon aren't easy to quanitify.
Characters who don't have any feats are generally useless in vs threads especially if they have nothing but hyperboles on their side.
However, some feats can be discredited if they are inconsistent, outliers (e.g. Master Roshi's moon busting) or were retconned (like everything involving Beyonder)