Simplify the following definition

The sensorimotor stage, from birth to two years old, is characterized by infants exploring the world through sensory observation and motor functions. They are egocentric and learn to manipulate their surroundings using their senses. The goal of this stage is to develop object permanence, where children realize that objects exist independently of their interactions with them. Symbolization occurs when infants can visualize an object mentally regardless of its physical location.

Infants from birth to two years old explore the world through their senses and motor skills. They are focused on themselves and learn how to interact with their surroundings using their senses. The main goal of this stage is to understand that objects continue to exist even when they are out of sight. As infants develop, they can also imagine objects in their minds even when they are not physically present.