The March 2008 issue of PC World had a story by Paul Boutin called 25 Days That Changed Everything.  They are the most significant moments in the the last 25 years of PC World.  Here they are.

   
       
       

September 29, 1986 Compaq surprised IBM by beating it to market with a competitively priced ($6499)computer with the new Intel 386 chip.  Suddenly IBM could no longer set the pace or price for PCs.
August 1, 1989 Microsoft Office made its debut as a $500 suite of popular programs (Word, Excel, and PowerPoint) on the Macintosh.  The Windows version came a year later.
February 19, 1990 John Knoll wrote a subroutine to show grayscale levels, his brother got him to turn it into a program which they called ImagePro.  Adobe retitled it and launched Photoshop.
May 22, 1990 Microsoft released a new multitasking version of Windows and sold about 10 million copies of Windows 3.0 establishing it as the dominant operating system for PCs.
May 24, 1991 The National Science Foundation made the decision to open the Internet to commercial use.  We now have a $100 billion a year marketplace that is still growing.
October 5, 1991 Finnish college student Linus Torvalds wrote a free "program for hackers by a hacker."  Linux allowed PCs to replace workstations and servers.
December 8, 1993 Mosaic became the first browser to imbed images in text rather than a separate window.  Their commercial version was called Netscape Navigator.  It has been said that when Netscape went public it created 200 millionaires in Silicone Valley.
April 12, 1994 A husband and wife lawyer team posted an advertisement for their services on 6000 Usenet discussion groups.  They claim 1000 new clients and $100,000 in income from an ad that was almost free.  Usenet wags called it Spam.
August 24, 1995 Microsoft launched Windows 95 and the Start button.  The default installation did not let you connect to the Internet.
September 4, 1995 Pierre Omidyar started something he called Auction Web which became eBay.  These days eBay supports an economy bigger than that of most countries.
March 1996 Palm developed a device that held 750 contacts and addresses, a year long calendar, and 100 to do notes in a pocket sized device they called the Palm Pilot 1000 ($299).
October 30, 1996 AOL changed from billing by the hour to a flat $20 per month for unlimited access and immediately overloaded their modems.  Within three years they  had 10 million subscribers and flat rate fees were the norm.
July 9, 1997 A decade after being fired by the company he started Steve Jobs sold his current company (NeXT) to Apple.  He became the CEO.
October 28, 1998 Bill Clinton signed into law the Digital Millennium Copyright Act.  It is probably the most unpopular law on earth brining into contention the Hollywood content owners and individual file sharing users.
January 19, 1999 Rim introduces a two way pager with a QWERTY keyboard.  The BlackBerry ($399) supported mobile text communication  The BlackBerry remains today's top selling smart phone.
March 29, 1999 A Word macro became the Melissa virus causing an estimated $80 million in damages on US businesses.  The author got a 20 month prison sentence but viruses are becoming even more prolific.
March 31, 1999 TiVo made video recording nearly effortless with menu driven scheduling and effortless playback from a hard disk.
January 1, 2000 Nothing Happened! 
April 3, 2000 The US declared Microsoft  a monopoly.  They are now a kinder gentler competitor, or at least a more cautious one.
July 26, 2000 Judge Marilyn Patel ruled Napster must be shut down.  (See October 28, 1998)
July 9, 2001 Webvan with its grocery delivery trucks and massive warehouses went bankrupt. They poster enterprice for the dot-com boom led the dot-com bust.
October 1, 2001 Apple introduces the iPod which will hold 100 albums transforming portable music players from tech trinkets to a lifestyle icon.
November 9, 2004 Because of Internet Explorer viruses, malware and bugs PC users were ready for a replacement.  Firefox is released to the public.
April 6, 2006 Unknow comic Judson Laipply posted a video which has been watched 70 million times.  You Tube turned PCs into TVs
June 29, 2007 The iPhone is released with a high resolution touch screen an estimated 2 million people have one.