I'm going to give this a try.
SCUBA = Self-Contained Underwater Breathing Apparatus
Since this is the first (maybe last?) thread I guess a good start would be asking anons some questions:
>Have you tried or thought about trying it?
>Are you certified (what certs, how many dives)?
>Experiences so far?
It's a pretty based hobby if you like getting wet. Staying and breathing underwater for longer periods of time exposes you to a completely different world and experience. You should at least try this once in your lifetime. Also, there's no talking underwater (except occasional hand signals), so you won't have to deal with nagging from other people except for a short period on the surface.
>Is it expensive?
Any hobby has its expenses. If you choose to own your own gear instead of renting it you'll quickly drive up quite a hefty cost. However, if you turn out to be an active diver the initial investment is usually worth it over time.
>Isn't SCUBA diving dangerous?
Yes, you could die with very little effort (hold your breath and ascend: boom, you're dead). You should keep this in mind every time you dive. The risk is worth it though, and quite low when it comes to recreational diving between or shallower than 18-20 meters.