At the age of 40 plus things that used to be easy to see are becoming blurred, your watch, small print, and threading needles. Presbyopia is Greek for old eyes which is a little harsh in our increased longevity. Focussing close up becomes far more difficult thus moving the paper away from your body helps in the early stages. If your are long sighted you will begin to see symptoms earlier which might also include distance problems as well. Short sighted people notice the onset later and often amuse their friends when they remove their spectacles to read.
This is a result of your fine tuning lens loosing its flexibility through age changes disallowing it to bulge and flex to focus the close image on the retina.
An addition known as the reading addition is added either to your distance specs or given as reading specs. Old methods of correction added a segment or bifocal to the distance pair for dual vision, but these have been superseded by the much more efficient progressive, varifocal or no line bifocal. There advantage being that they give the user multiple focus points across a wide range of close work distances.
Onset & Progression
Starts around middle age and progresses till full addition correction is required at around 65.