For an industry supposedly worried about making its products "user friendly," the personal-computer industry has certainly made a hash of things in designing keyboards.

IBM has been the worst offender, but Apple has made its contributions as well.

The trouble started with the original IBM PC in 1981. The keyboard, like most IBM keyboards, had a solid feel, but the layout was bizarre. The all-important "Enter" key was in the familiar location, where the "Return" key is on most electric typewriters.

But instead of the large L shape familiar to typists with IBM Selectrics, the PC keyboard had a narrow "Enter" key, made smaller by a tiny raised key cap. The oft-used backspace key, enlarged on Selectrics, also had a tiny key cap on the PC.

What's more, both Shift keys were too small, smaller even than the "Caps Lock" key located just below the right Shift key.

There was no "Caps Lock" indicator, so if you accidentally hit "Caps Lock," you were likely to type capital letters before realizing what your flying fingers had done. There was a separate numeric keypad on the right, but several of the number keys doubled as cursor keys. If you were entering numbers in a spreadsheet, you had to keep hitting a Shift key to move the cursor, then hit it again when finished.

IBM could have made the numeric layout a cinch to master by putting the numbers in the same place as on a telephone. But instead, they were laid out in exactly the opposite pattern, and that pattern is now ingrained as the industry standard.

One enterprising firm, Keytronics of Seattle, did a thriving business with a substitute keyboard, the 5151, which had a separate set of cursor keys and a larger, though still not large enough, "Enter" key. Keytronics also had the function keys in a row across the top, whereas IBM had them in two vertical rows at the left.

The IBM layout made better sense because it put the function keys close to the "Control," "Alt" and left "Shift" keys, with which they are often used in combination. Function keys across the top mean most such combination keystrokes require both hands.

IBM brought out its PC-AT in 1984 with a new keyboard. It was much better in some ways. There was a large L-shaped "Enter" key. The shift keys were larger as well. There were lights to tell you if the "Caps Lock," "Num Lock" and "Scroll Lock" keys were active. But the "Escape" key, located in the upper left corner on the PC keyboard (and on many other computer keyboards as well), had been moved to the upper right. The Backspace key was still too small, and there were still no separate cursor keys.

But it was a definite improvement and became an industry standard, used by nearly all IBM clone manufacturers.

One exception is Tandy, which uses a keyboard on its popular 1000 series that is confusingly unique. Function keys are across the top. You can adjust to that, but other keys, such as the often-used "Alt" and "Delete," are nowhere near their place on other IBM-standard keyboards.

Meanwhile, Apple had brought out its Macintosh, whose keyboard had a nice feel and a large "Enter" key, but no cursor keys at all. It was intended to be used with a mouse. If you didn't want to use the mouse, tough.

That has been corrected in more recent versions of the Macintosh, but since the cursor keys are not supported by a lot of software written for the original, they often don't work. The original Macintosh had no numeric keypad.

When IBM brought out later models of its AT and its new PS/2 series, there was an opportunity to introduce a keyboard that undid mistakes of the past. To an extent, it did, but it also makes some new blunders.

The "Escape" key is back in its old position, upper left. Function keys, for the first time, are across the top, which is not an improvement if you're used to having them at the left.

There is a separate set of cursor keys, but the "Enter" key has actually shrunk. And, worst of all, the "Control" key, which has been located above the left Shift key on nearly every computer since the CP/M era, has been inexplicably moved to where the "Alt" key used to be. The "Caps Lock" key is in its standard place.

Unfortunately, most clone makers and substitute keyboard vendors have simply followed IBM's lead, though some are making their keyboards with a large L-shaped "Enter" key. And many are still offering the old AT layout, which remains popular.

If you are looking for a substitute keyboard, Datadesk of Van Nuys, Calif., and Northgate Computer Systems of Plymouth, Minn., make good ones. So does a Taiwanese firm called Dah Yang, whose keyboards have the brand name Unitek.

Watch out for BTC keyboards, used on many IBM clones. They have a mushy feel.Brit Hume is a contributor to the Washington Post Writers Group. Hume is an ABC News Capitol Hill correspondent and the founding editor of a computer newsletter.