Sensation is the function of the low-level biochemical and neurological events that begin with the impinging of a stimulus upon the receptor cells of a sensory organ. It is the detection of the elementary properties of a stimulus.
Perception is the mental process or state that is reflected in statements like "I see a uniformly blue wall", representing awareness or understanding of the real-world cause of the sensory input. The goal of sensation is detection; the goal of perception is to create useful information of the surroundings.
In other words, sensations are the first stages in the functioning of senses to represent stimuli from the environment, and perception is a higher brain function about interpreting events and objects in the world. Stimuli from the environment are transformed into neural signals which are then interpreted by the brain through a process called transduction. Transduction can be likened to a bridge connecting sensation to perception.
Gestalt theorists believe that with the two together a person experiences a personal reality that is other than the sum of the parts.
Sensation is the process by which our senses gather information and send it to the brain. A large amount of information is being sensed at any one time such as room temperature, brightness of the lights, someone talking, a distant train, or the smell of perfume. With all this information coming into our senses, the majority of our world never gets recognized. We don't notice radio waves,