Just about 30 seconds ago, I slipped the Apple Writer word processing diskette into my disc drive, turned on the green/phosphorous video screen and threw the main switch on my Apple II Plus personal computer.

Now comes the hard part.

In the coming months, you and I are going to try to learn about personal computers, things like what they can and can't do and what they cost. Pretty basic stuff, really. And pretty important, too, since we're going to be told more and more frequently that we need one.

Maybe the perfect person to write this biweekly column would be some computer whiz steeped in all that jargon about bits and bytes and booting and other such. Someone who undoubtedly would be able to teach us right off the bat to program our computers to turn off the light switches and tuck the baby in at night. Pretty darned impressive stuff.

But chances are that you're one of the millions who don't know yet if you want a computer turning your lights on and off--much less tucking in the baby. As a matter of fact, even though you're intrigued by the small computers, you probably doubt seriously whether you could run one at all.

Well, not to put too nice a point on it, join the crowd. I ain't no computer whiz. As a matter of fact, I distinctly remember how thankful I was in college that computer studies weren't required for a degree (I was very much into 18th century British literature--and I'm sure I needn't impress upon you how useful that is).

Those uneasy feelings are exactly why someone like me is writing this column. At work, I type on a fancy keyboard that feeds into a computer--but they don't let me get close to the real thing. So, when it comes to computers, I am the Common Man, and I can assure you of one thing: If I can understand it, then you can, too.

Fact is, most people are like me: They are at once intrigued and intimidated by computers and computer jargon. But there's a slight problem with that, as quaint as it may be. You see, all of us ignoramuses are going to be left behind unless we take some time to understand what the computer industry is about to do to our lives.

Like it or not, computers are here to stay, and if you thought they were too involved in your lives already, look again. In the next couple of years, you're going to find them in the homes of friends and in the offices of small businessmen.

The reasons are simple: they're tiny and they're approaching being affordable and they're powerful. How powerful are they? Let me give you an example.

Right now, as I write, the federal government is trying to decide whether to let the Communist Chinese have an Apple computer not much different from the one I'm writing on. Seems that Dulles Airport customs agents confiscated an Apple from a shipment being made last fall to Peking by the Chinese embassy. The matter is being prosecuted, but officials refused to discuss the case.

The concern is that an Apple in the hands of the Chinese could be a national security threat.

You and I aren't directly concerned about strategic uses of an Apple, I'm sure. No. The reason you and I are taking a closer look at them is because we're seeing the likes of Dick Cavett hawking Apples on TV. And the reason for that is--and I turn to the delightfully imaginative phraseology of the computer industry--personal computers have become "user friendly."

That means that computers that once spoke only intimidating-sounding languages like Pascal and BASIC have been taught to speak English, almost like you and me. Let me give you and example. When I turned on my computer a few minutes ago, it flashed on the screen the following:

"You may choose from one of the following . . . " It then offered me a handful of options, also in plain English.

Why computers are being taught plain English is largely the result of the remarkable reductions in price and size that computers have undergone in the past decade. Suddenly, computers that would have cost as much as a small house and been large enough to fill most of a garage are within a lot of ordinary people's reach--physically as well as financially. Now you can buy a pretty complete home unit that's about the size of an electric typewriter for around$1,000.

Thanks to that dramatic change, our fates were sealed. The minute computers became small and relatively inexpensive, computer whizzes began developing programs for them that ordinary people could understand.

The rest, as they will someday be saying, is history.