Shortsightedness is a very common condition. There is a small tendency to heredity. Shortsightedness normally starts at the end of school age and deteriorates with time. After the age of 25-30, the development of nearsightedness stalls.
The main symptom is impaired distance vision. Therefore, it is difficult to see clearly from a long distance.
On the other hand, it is not a problem to see things close up and to read. As shortsighted, you will have a tendency to screw up your eyes in order to see more clearly. This can lead to tired eyes and tension headache.