Can staring at a computer screen for hours a day really damage your eyesight? any answers appreciated!

No: However, prolonged computer work can dry the eyes and cause irritation as the blink rate does down. Use artificial tears. The focusing of the eyes can be affected so take a break every hour or two looking in the distance. Make sure your glasses presciption is up to date to avoid tired aching eyes. Keep the brightness down to avoid light sensitivity. Sometimes a little larger font will help.