By being able to select an appropriate typeface, include italics and add other refinements, you are able to make the final text more pleasing to the eye and easier to read.
But the appearance of the document is only a minor consideration. What makes the word processor such a vital tool is that it makes it easier to be a better writer. And when writing is such an difficult task, anything that makes it easier must be worth its weight in gold.
It makes you into a better writer because it helps make you into a re-writer - and in this business, second, third, fourth, eighteenth thoughts are always best. When you "write in light", you can constantly draft and re-draft, add and delete text, check the punctuation, remove cliches ("worth its weight in gold", for example) and safely reunite (some) split infinitives.
When children are using pen and paper, they find that redrafting is a terrible chore; so, rather than make the effort, they will convince themselves, if not their teacher, that their first version is the best they can do.
On a word processor, making corrections is positively enjoyable. So pupils are encouraged to think about what they have written and quickly see the improvements they could make.
The Delete key has a marvellously liberating effect. Children know that when they are writing they can take risks, safe in the knowledge that if they don't like anything that they have written it can always be made to disappear.
It's silly to imagine that pen and paper are going to be replaced in the foreseeable future. But it's also worth remembering that novelists, playwrights, journalists and other professionals increasingly regard the word processor as the "natural" way to write. Those management types who used to dictate to shorthand typists are now far more likely to be typing their own twaddle on notebook computers.
There is a remarkable range of word processors that are especially suited to the classroom. Some, for example, actually "speak" the words as they are typed. Others second-guess the word the child has in mind, once the first couple of letters are typed, and offer a selection of likely alternatives from which the child can choose.
Any decent word processor will have utilities from which teachers as well as pupils can benefit. A spell-checker, for instance, will rid the text of typing errors and howlers; an on-screen dictionary and thesaurus can make it easier to find exactly the right word.
It's possible to programme the software so that one key stroke will type out the words or phrases that you use frequently. A simple command and the machine will search the entire document for a particular word and automatically substitute any other that you choose.
Teachers have every right to be sceptical about the ludicrous claims that have been made for IT. But those who are prepared to put word processing to the test will quickly discover the countless ways in which it could help them to perform more effectively.