Oahu is easy to navigate. A complete selection of transportation options — and a fairly simple highway system — give visitors many choices. Your final decision will depend on your plans for exploration.
If you're staying in Waikiki and don't intend to move much farther than the beach, you won't need to rent a car. Most hotels have shuttle services to and from the airport, and TheBus or trolley systems can deliver you to outlying shopping malls or major attractions. Also bring your walking shoes; Waikiki is small enough to hoof it most anywhere.