Each of Hawaii's main islands has its own personality. Oahu (Honolulu, Waikiki, Pearl Harbor) is the most developed with city vibes plus North Shore surfing. Maui offers world-famous beaches like Wailea and Kaanapali, the scenic Road to Hana, and Haleakala sunrise. The Big Island has active volcanoes at Hawaii Volcanoes National Park, black sand beaches, and the resort coast of Kona. Kauai is the 'Garden Isle' with the dramatic Napali Coast, Waimea Canyon, and lush Hanalei Bay. Island hop via inter-island flights (Hawaiian Airlines, Southwest), typically 30-50 minutes between islands. Plan 3-4 days minimum per island. Best months: April-May and September-October for fewer crowds and lower rates.