Fishing kayaks are wider, use a sit-on-top design, and are customized to accommodate the gear needs of an angler. Recreational kayaks feature a sit-inside design and are designed for general use. They tend to be a little more agile on the water and don't have as many features.
Kayak fishing is worth it. It is budget-friendly, versatile, and gives better access to fish. Fishing kayaks are also customizable, portable, and do not require any launch ramp. However, kayaking has its cons, including risks of injury from water creatures, harsh weather conditions, and backaches.