1-)Explain how optical and non-optical aids help visually challenged persons to develop their skills to a higher level.

2-)What is braille system ? how it helps the visually impaired ?

2) braille system was invented by LOUIS BRAILLE. this system is based on dots which represents numbers and alphabets which helps visually challenged { blind } to read. this is known as braille scrpit. there are 63 patterns of braille script