There are different refractive errors. We talk about far-sightedness when a person sees well close up and the distance is unclear. This is corrected with a plus in the glasses. If a a hig plus is needed it can cause reading problems and give headaches. Simple reading glasses can have a great impact. Children can participate in school and adults can do their work.
We talk about near-sightedness when distances are unclear but close up can be seen. This is corrected with a min in the glasses. Nearsightedness can have major consequences for a child, participation in school can be very difficult. Also for adults the consequences are great: not being able to work, and greater chances of accidents.