Ultilingo.com defines
the layout as "the act of diving while running in order to catch a disc out of ordinary reach." I think
CSTV defines it better as "when a player dives to catch, block, or intercept the disc." If you are an exceptional player though, you will catch the disc even if you are playing defense to prevent the event of it still flying/floating into the offenses' hands. I say "exceptional" because not only is it hard to get to a disc that wasn't intended for you, but if you catch it you have to then throw it. Normally the only time the offense is going to be thrown the disc is if they are able to lose their defensive mark. This means that the defensive player has to be able to catch back up and get in between the offense and the disc. If the offense is good, they know not to stop running until they have caught the disc. The defense is normally only left with one option now. They must layout (go
ho) passed their offensive mark without fouling to get a hand on the disc. Being able to catch it in this situation is very difficult. I'd say you are lucky (good if you will) to get a hand on it. But to catch it to ensure that the offense has no chance of getting it, is a different story. The story would be of an exceptional ultimate player. I will add one more level of exceptionality to this story: once caught that person would preferably be a good handler as well, so as to
conserve their greatness.
I'll define a few different categories of layouts: the horizontal layout, the vertical layout and the unnecessary layout. The horizontal layout was already explained above. The vertical layout is pretty much the same as the horizontal, except that you jump more upward at an angle (not really vertical). The only person I've really seen do this well is Ben Parris, when trying to catch a disc that was flying passed him at about shoulder/head height. The unnecessary layout should be self explanatory, but I'll explain it anyway. It is when a player dives to catch the disc that was within ordinary reach, sometimes in order to show off. These can be dangerous because the player is increasing the difficulty of catching the disc. I only refer to unnecessary layouts when the player is on offense. However, when on defense, it can be a safety measure to make sure the disc is D'ed up. When someone lays out, almost instantaneously they gain a full body length of ground, increasing their chances of making a play on the disc. However, it is not as imperative to catch the disc when playing defense, so I would call this a safety measure an not necessarily unnecessary.
Sometimes after I layout for a defensive play I think that maybe I could have gotten there without the layout. It's a close call and hard to tell a lot of the time unless someone is filming or something, but I say go for it to be safe. Ming told me the same thing. Plus, if you don't you might get yelled at by people saying "a good layout woulda had it."
Learning to layout is hard. I remember being scared to do it before I learned. It doesn't look pleasant hitting the ground flat on your stomach/chest, but you'll realize that it is nothing you can't get right up from and continue playing. All that I can say is that you have to do it to overcome your fear. Once you do it you won't be afraid anymore. It really doesn't hurt, most of the time. When all your concentration is on getting the disc you won't feel the ground at all.
Look at Shaggy here. Do you think he's worried about the ground?