Every typewriter has it’s own type “signature”, resulting from the age of the keys, the manufacturer, whether they are in vertical and horizontal symmetry, force of impact, etc. Many court cases have hinged on establishing the source of the type signature. The purported Obama birth certificate has a type signature that is quite different from the Nordyke twins birth certificates supposedly produced a couple of days subsequent to Obama’s.
Obviously it’s possible that a different machine was used for the Obama certificate, but it appears to have been typed on a much older piece of equipment. Look at the capital K and capital S. They don’t line up in symmetry with the lower case letters or other capitals. The type on the Nordyke documents including the K and S are in noticeably tighter symmetry.