Kettlebell exercises are some of the best exercises you can include in your WODs. Kettlebells are extremely versatile if you compare them to the dumbbell, the dumbbell wins when it comes to a low learning curve. The kettlebell wins when it comes to versatility and benefits.
The main difference between a kb and db is that the kb has a handle and the weight distribution is completely different. The handle is what allows the kettlebell to be so versatile, the weight can be pressed, snatched, swung, jerked, moved around the body, and used for any exercise imaginable where the db and bb could not be used.
One of the best resources about kettlebell training and kettlebell workouts is without a doubt Cavemantraining. Make sure to check out the website and YouTube channel with hundreds of kettlebell WODs.