I began writing these Personal Technology columns 20 years ago, in October 1991, with the aim of reviewing computers and other digital products for average, mainstream users. The first line of my first column was: "Personal computers are just too hard to use, and it's not your fault."

Consumer technology has come a long way since that day. Digital gadgets—then too often designed by techies for techies—have become essential to our lives, and much easier to use, even if we still need the Geek Squad and the Genius Bar more than we should. And the pace of change has been mind-boggling.

In 1991, most consumer computers didn't have built-in audio beyond just the ability to beep. Most lacked any way to communicate with the outside world—even via a slow, dial-up modem. The Internet wasn't available to most people. Search engines and social networks didn't exist.

Mobile phones were huge bricks. Digital cameras for consumers cost a fortune and took monochrome pictures. Digital music players and video recorders, e-readers and tablets were nowhere to be found.

So, this week, I decided to take a look back at some of the game-changing products that appeared in this column over the past two decades and propelled us from that primitive landscape to today's interconnected digital world. This list of milestones is just a sampling; yours might differ. Also, since I write for average consumers, the list is weighted towards consumer products, not gadgets for geeks or corporate use.