Here a while back someone was looking for a font that looked like it was done on an old typewriter. I came across one today that is pretty neat..if anyone still wants it...
That looks more like a dirty typewriter font than an old one.
Your machine probably is hardcoded with the Courier font, which was invented by IBM fifty years ago for its typewriters. It's a monospaced font that faithfully replicates a typewriter. There are also plenty of other, even older typewriter fonts available from many font foundries.
If you want to really replicate the look of a typewriter, get a daisy-wheel printer which uses a type wheel and a ribbon.