We must learn and practice all types of yoga, step by step, in order to succeed fully at the goal of self-realization. They all compliment each other and together create a well-balanced approach towards spiritual success.
In our ordinary daily lives we are very clever and use often our intellect to satisfy our senses; for example we spend hours by altering the natural flavor of food by cooking and spicing so that it will taste and look better, or by combining it with certain drinks so that it will be even more tasty. All the senses we bring together by unconsciously, but fully applying our physical mind. And then, after a while, the happiness is gone and we have to start again to satisfy our senses.
But in Raja Yoga we are stopping the outgoing senses and focus on stilling the mind. Raja Yoga is called 'Citta vritti nirodha.' Stopping the mental waves. In Hatha Yoga we stop the pranic waves so that the mental waves will stop. In Kundalini Yoga the senses are brought together and the energy will not move outward. With that, thought will be in a higher vibratory level. All these experiences are one and the same, only the point of view is different.
There is really no difference between Kundalini Yoga, Hatha Yoga, Mantra Yoga, Laya Yoga, and Raja Yoga. Each Yoga may emphasize certain points, but they are not basically different from each other. They are all part of Ashtanga Yoga (the eight-limbed Yoga): yama, niyama, asana, pranayama, pratyahara, dharana, dhyana and samadhi.