MOVIES WERE invented for people who don't have time to read books.

Now there are movies for people who don't have time to watch movies.

If 225 minutes, the original length, sounds like too much to expend on a viewing of "Lawrence of Arabia," you can now buy a version that takes about one-tenth the time, and you can watch it in the privacy of your own home.

And if you just couldn't get enough of that super-duper megahit of the '70s, "Star Wars," now you can take eight minutes' of it home with you and play it over an over until you just can't stand it any more.

While America waits, with surprising patience, for the long-promised video disc, and while few can shell out the required moolah for a video cassettee machine, movie companies like Columbia and Universal are taking advantage of the home entertainment boom by selling radically shortened versions of their old and even semi-new movie classics and clinkers.

For about $50, Columbia will sell out-right Super-8 sound versions of such biggies as "Lawrence," "Born Free" and "The Caine Mutiny." Sales of projectors on which to show such films are increasing, the projectors are quality isn't all that bad, at least as compared to the visual mush of many shopping center houses.

Although 20th Century-fox, the happy "Star Wars" studio, doesn't have its own 8mm division yet, a New York company called Ken Films hopes to have its 8-minute "Super 8" reel of "Star Wars" highlights - in color sound, color silent and black-and-white silent versions - in stores this week. The films will sell for about $25, and contain highlights from two main scenes, including Luke Skywalker's and Hans Solo's spectacular aerial fight with forces of evil after their escape with the princess and the two cute robots from the Death Star.

The ascent into hyperspace and the film's climactic battle are among the many scenes not in the home version, but it's still unusual because the film itself is in current theatrical release. Usually movies don't make it to the living room circuit until they've also been sold to television.

The relatively new genre of Super 8-mm quickie cinema represents a number of breakthroughs itself. For one thing, and this is surely a break-through, it gives families something to show their bleary-eyed guests besides those barely ulluminating and barely illuminated shots of Uncle George sitting on his horse.

And there are the somewhat dubious giant-steps-for-mankind: Super-8 versions give movie companies one more way of squeezing pennies out of their old films. And they provide an alternative to television as a means of ruining motion pictures.

This is what comes of living in a condensed age.

What do you get for your money? Roughly, the movie equivalent of a postcard that reminds you of a vacation. Or one of those "greatest classics" record albums that eliminates all the messy variations and leaves you with just the theme.

The 20-minute edition of "Lawrence of Arabia," from the Columbia 8-mm catalog, certainly does move right along. Zip, zip, zip. Sluggish it isn't Narration has been added to cover the gaps, or craters, or Crater Lakes, in the story. "Capt. Lawrence arrives on assignment for England," says the narrator as the films begins, its CinemaScope shruck to a dart board.

In this version, T.E. Lawrence does not die in a motorcycle crash. He doesn't die at all. And Jose Ferrer never comes along to pinch him in the oasis. Jose never comes along, period.

"We need a miracle," says Alec Guinness, and that's the last we see of him. Zip, we're in the desert and Peter O'Toole, as Lawrence, is saying, "Aqaba is over there," to which Omar Sharif replies, "Yes! Aqaba!" On to Cairo. And then on to Damascus, though a few Turks get in the way.

Narrator: "With the Turkish forces destroyed, the road to Damascus is clear."

Sign with pointing arrow: "Damascus."

What goes up may come down faster than one thinks, and in the 8-mm "Bridge on the River Kwai," originally 161 minutes, the bridge is built and exploded almost as quickly as William Holden can say, "The only important thing is how to live like a human being!"

Early in the film, Sessue Hayakawa slaps Alec Guiness in the face with the Geneva Convention and locks him in the hot box. "Weeks passed," says the narrator. Alec is out in two shakes of a lamb's tail. Make that one shake Zip, the bridge goes up. Zip, and Alec is saying, "Blow up the bridge?" And "What have I done?" He might indeed wonder.

"Madness! Madness! Madness!" says an actor in the aftermath. They've left in all three madnesses.

When it comes to musicals, a 20-minute version doesn't sound so unsettlingly abrupt as those expurgated epics. After all, they can edit out all those silly plots and leave in those great old Hollywood musical numbers, right?

Wrong.

"You ain't heard nothin' yet," says Larry Parks in "The Jolson Story," but you don't hear much more than nothin' as the 8-mm version continues. About 100 minutes ended up on the cutting room floor. Still, there are a few bars of "You Made Me Love You." "Mammy," "April Showers" and others. When Al's parents finally appear 15 minutes into the 20-minute film, they do not get to hear "The Anniversary Song," even though it's their anniversary.

More drastic still are the cuts in "You Were Never Lovelier," once a 97-minute romp punctuated with such Jerome Kern songs as "I'm Old Fashioned." The punctuation has been dropped, Fred Astaire only gets to sing one line of the little tune, and he and Rita Hayworth don't dance until the very last minute of the film.

"You," sings Fred at the finale, "were never lovelier than you" With a blurp, the movie's over.

One film at least benefits from this hatchet job: "Earth Vs. the Flying Saucers" There never was much to this 83-minute '50s sci-fi fantasy except the final 10 minutes in which Washington is made into mincemeat by special-effects flying saucers.

Thus through the magic of Super 8, we can now see the Capitol Dome sliced like a peach and not have to sit through a lengthy explanation of how this came to pass. It always seemed a trifle incredible, anyway.

Steve Schiffer, director of marketing for Columbia's 8-mm division, says business is good for the films, which are also available in silent versions.

"You're not getting the whole movie and nobody claims you are," Schiffer says. "Most everybody now is programmed to a half-hour TV segment, anyway. What you get here is a 20-minute entertainment package."

So - we're programmed, are we?

Old "Batman" serial chapters "sell like crazy," says Schiffer, and other hot item is the quickie edition of the toney porno picture "Emmanuelle."

There are also cartoons ("Love Comes to Maggo"), travelogues ("Wonderful Israel" ) and a vast selection of Three Stooges featurettes. Since these were shorts in the first place, nothing had to be cut. So though 80 minutes is missing from "On the Waterfront" and about 100 from "Mr. Smith Goes to Washington," The Three Stooges in "Hula La La" runs length.

Some things are sacred, after all.