Some people get used to seeing things in a certain way so that they ignore a progressive vision problem. Causing many to squint a lot, and end up with unnecessary eye strain at their computers.
Do you see Albert Einstein while sitting a normal distance from your computer? Then you are seeing things as you should.
Do you see Marilyn Monroe?
Then you should probably be wearing glasses or contacts.
Original image Created by Dr. Aude Oliva, MIT http://cvcl.mit.edu/hybrid_gallery/monroe_einstein.html