The formal 4-bowl style of eating meals comes from China. Originally, in the Buddha's time, there was only one bowl. The 4 bowls are symbolic of the four elements - earth, air, fire and water, and also of Buddha, Dharma, Sangha and Mind.
The formal meal is an important part of practice. Everyone eats together in silence in the Dharma Room. Following the steps of the formal meal helps the mind stay completely aware and focused. It also teaches us to be mindful while eating - always know how much is enough; think of others when sharing food; do not attach to taste and sight, eat only to support yourself in practice, and not to your satisfaction.
In the Kwan Um School of Zen, we use this style of meals only during retreats: YMJJs or Kyol Ches.
There is a certain ceremonial format for this meal, involving all four bowls, chopsticks and spoon. We begin with opening the bowl set, then serve each other, eath together, wash the bowls with tea, rinse them with water, offer some water to other beings, then dry and repack the bowl sets to the state we started from.
The Head Dharma Teacher or any senior student will help you through this for the first time, and as many times as you need afterward during the retreat.