Back in the day, tables were the only option. Today, the majority of recreational divers wear a personal dive computer and they should.
A dive computer tracks depth, time, speed of ascent, and no-decompression limits in real time. Dive tables are a fixed calculation. If you go shallower mid-dive, the computer recalculates. Tables are set before you get in.
Wrist-mount computers are what the majority of divers buy these days. They're small enough, easy to read, and you'll use them as a daily watch between dives. Console-mount models are an option but fewer buyers go that way these days.
Budget computers run about a few hundred dollars and do everything the average diver requires. They give you depth, time, no-deco limits, dive logging, and sometimes a basic apnea mode. Mid-range gets you air cairns dive computers integration, better screens, and more nitrox options.
What buyers forget is how the computer handles. Certain models are tighter than others. A cautious setting gives you less NDL. More aggressive settings extend time but at reduced margin. Both work. It comes down to personal preference and how experienced you are.
Talk to people at a local dive store who dives with a few different brands before buying. Good dive stores will have real-world feedback on what works versus what's hype. Most good dive stores have buying guides and honest reviews on their websites as well