(KCBS) – Thirty years ago tomorrow, IBM unveiled the personal computer that some say changed the world.

It was the 5150 machine that made a big leap forward.

CNET Editor-at-Large Brian Cooley said unlike all the stuff that comes from Apple today, which is proprietary, the origrinal IBM PC was made from off-the-shelf components that other companies already built, which means there were clones. Many companies could make the same product at a competitive price.

Apple didn’t believe it was going to be a big hit, Cooley described the interesting history. It was a skunkworks project in Florida away from IBM headquarters and they were already coming from behind trying to catch up to upstarts like Apple.

Now, time’s are changing and PCs are starting to take a back seat to laptops, tablets and smartphones. These products are just more intuitive and something you can always have on you, Cooley explained, so PCs are no longer the hottest items.

Smartphones did outsell PCs for the first time last year.

You can hear his Tech Watch report Tuesdays and Thursdays at 1:50 P.M. on KCBS All News 740AM and 106.9FM.

(Copyright 2011 by CBS San Francisco. All Rights Reserved. This material may not be published, broadcast, rewritten, or redistributed.)