The truth is that the ideal should be a combination of exercises. In a proper routine thinning should include both aerobic exercise (running, jumping, cycling) and strength or anaerobic exercise (lifting weights). The combination of both can produce great results.
The aerobic or cardio are ideal for improving your fitness and burn fat while you are doing. While anaerobic or strength exercises help you burn fat even when at rest as they help to increase metabolism. Having adequate muscle mass will help to speed up metabolism, so you need to do strength training and bodybuilding.