Already our skin allows us to perceive the texture different materials as well as the temperature objects, by the pressure differences, capturing the variations of the thermal energy and also the pain sensations.
We can feel the softness of a peach's outer shell, the warmth of a child's body that we hold in our lap, and the softness of the skin of a caressing body. Without this information, our feelings of pleasure would be diminished, we could get burned or hurt ourselves often. This form of perception of the world is known as tact.
Touch receptors perceive pressure differences (pressure receptors), translate information received by contact with different chemicals, and also perceive the transfer of thermal energy from one body to another (heat receptors).
The visually impaired can read texts, figures, musical notes, etc. and also write their own texts by the system Braille. The alphabet of this system consists of small protruding points on a sheet of paper. The reading is done by light fingertip pressure on the points to perceive their position and number. Writing is accomplished by punching the paper by an appropriate instrument. This is possible due to the high concentration of pressure sensitive receptors at the fingertips.
The braille system is used internationally and in all languages. It allows the representation of letters and various other signs.
Our senses inform us in various ways about what is happening around us. We can see and hear, smell and taste. We can feel the texture and temperature of the things we touch. Our senses are impressed by matter and energy and thus our organism comes into contact with the environment.
However, our sense organs are limited, perceive only a certain amount of light, sound, and so on. Likewise, our body supports only a certain amount of pressure. But man began to create instruments to broaden his perception of the world, being able to see smaller and larger objects, understand and identify ultrasound and infrasound. With the possibility of a new look, man was finding new problems, raising new hypotheses, reaching new conclusions and knowing new realities.