Tables used to be the only option. These days, the majority of recreational divers dive with a wrist-mount computer and it makes sense.
Your computer monitors your depth, time, ascent rate, and no-decompression limits in real time. Tables can't do that. If you go shallower during a dive, it updates. A table can't.
Wrist computers are what the majority of divers use these days. They're compact, easy to read, and you'll wear them as a regular watch too. Console-mount models are still around but not as many people go that way these days.
Entry-level computers run about $250-400 and cover everything most divers needs. They give you depth, bottom time, no-deco limits, dive logging, and usually a basic apnea mode. The $500-800 range gets you wireless air monitoring, better screens, and additional gas compatibility.
Something people don't think full report about is conservatism settings. Certain models are tighter than others. A cautious computer results in less bottom time. Liberal settings give more time but with less margin. It's not right or wrong. It comes down to what you're comfortable with and your diving background.
Worth talking to the staff at a dive shop who uses multiple models before you decide. Staff will give you a straight answer on which ones hold up versus what's marketing. Decent dive shops have product guides and comparisons online as well