Though specific learning disabilities have probably existed as long as human learning itself, they were "discovered" only at the turn of the 19th century, and have become a pressing social problem in the developed countries only since the 1950s. As the demands on education in the developed countries increase, so does the problem these disabilities represent; and as the developing countries turn to education to help them "catch up" and begin to make schooling mandatory, learning disabilities will acquire importance for them as well. Such disabilities are thus becoming a worldwide concern.