Concepts

You can't edit or modify the output from a typewriter without retyping the whole document. Want to change just one word in a 10 page term paper? With a word processor your document is saved on a diskette. To make a change, you simply load your document back into the word processor, make your change, and print.
Both a word processor and a typewriter allow you to create documents with a consistant typeface.
A typewriter is a physical machine, the word processor you are learning in this class is software that runs on a more general machine called a computer.
Word processors evolved from typewriters. Electricity was first added to typewriters to 1) reduce the amount of effort that is needed to strike a key, and 2) allow for faster typing by reducing the minimum amount of time necessary between key strokes.
Typewriters have one typeface (or font). It usually looks something like this. Most word processors support multiple typefaces and various character attributes such as bold, italic, and character size.

The Classic Typewriter Page Comprehensive source for information about classic typewriters, including the metaphysical significance of early typewriters.