Years ago, dive tables were how everyone dived. These days, nearly all scuba divers use a personal dive computer and it makes sense.
A dive computer tracks your depth, time, speed of ascent, and no-decompression limits in real-time. Tables can't do that. When you go shallower mid-dive, it updates. A table can't.
Wrist-mount computers are what most people buy now. These are small enough, readable underwater, and you can use them as a daily watch between dives. Hose-mounted computers are available but not as many people pick them anymore.
Basic computers run about $300-odd and do everything most divers requires. Features include depth tracking, bottom time, NDL, dive logging, and often an entry-level freediving mode. Mid-range gets you air integration, improved readability, and additional nitrox modes.
What people forget is algorithm differences. Certain computers are tighter than others. A cautious computer means less NDL. Looser ones give more time but at a thinner safety margin. It's article not right or wrong. It comes down to what you're comfortable with and how experienced you are.
Ask someone at a dive shop who's used multiple models first. Good dive stores will offer a straight answer on what works and what's marketing. Most good dive stores have buying guides and rundowns on their websites too