Tables used to be how everyone dived. Today, nearly all recreational divers wear a dive computer and it makes sense.
Your computer calculates your depth, bottom time, speed of ascent, and no-deco limits in real time. Dive tables are a fixed calculation. When you move between depths mid-dive, the computer recalculates. A table can't.
Wrist computers are what most people go for now. These are compact, easy to read, another article and you'll wear them as a regular watch between dives. Hose-mounted computers are available but not as many divers pick them anymore.
Entry-level computers start around a few hundred dollars and cover everything the average diver requires. You get depth tracking, bottom time, NDL, dive logging, and usually a basic freediving mode. Mid-range includes transmitter compatibility, better displays, and extra nitrox modes.
Something people don't think about is how the computer handles. Some computers are more conservative than others. A conservative computer means shorter bottom time. Looser ones give more time but at a thinner safety margin. It's not right or wrong. It's what you're comfortable with and experience level.
Talk to people at a dive shop who's used various computers first. They'll have a straight answer on what's good and what isn't just marketing. The better Cairns dive stores put out gear reviews and comparisons on their sites too