Early computers generated text the way a typewriter would - character by character, one line at a time. Users had a limited number of characters, with no variation in appearance. The Mac was one of the first to approach displays like a TV: Text gets incorporated into a graphic that the computer projects on the screen pixel by pixel.
With those tools, would-be publishers could change fonts, adjust typeface sizes and add attributes such as italics. They could also mix images with text. The earliest Macs popularized "what you see is what you get," or WYSIWYG; formatting on the screen largely reflected how the page would look in print. Instead of going to a professional printer, anyone could simply design and print newsletters on a Mac.
Of course, the Mac's success was never guaranteed.
Initially, many people "thought it was a waste of time and a gimmick," says Dag Spicer, senior curator of the Computer History Museum in Silicon Valley.
He says long-time computer users already knew how to perform computing tasks "very efficiently with just two or three keystrokes. It might have been more efficient for them than to use a mouse."
The Mac didn't run software for the company's Apple II computer, so there was little people could do with it until Aldus - now part of Adobe - released PageMaker publishing software in 1985. The original Mac had little memory and a small screen, and it lacked a hard drive. Although the Mac's processor was fast for its time, much of that power went to the graphical interface instead of tasks common for research and commerce.
With the Mac came "the dawn of the notion of we can waste computing power to make it easier for people," says Jim Morris, who worked on the Xerox Alto before joining Carnegie Mellon by the time the Mac came out. "The Macintosh was not a business machine."
Tim Bajarin, a Creative Strategies analyst who has followed Apple for more than three decades, says he was baffled, yet intrigued when he saw the Mac's unveiling at an Apple shareholders meeting in 1984.
"This really was a complete departure from the computing that we knew," he says. "None of us had any clue what its potential would be."
In fact, despite its radical interface, sales were lukewarm. For years, it was mostly a niche product for publishers, educators and graphics artists. Corporate users stuck with IBM Corp. and its various clones, especially as Microsoft's Windows operating system grew to look like Mac's software. (There were years of lawsuits, capped by a settlement.)
Now the world's most valuable company, Apple Inc. nearly died in the 1990s as its market share dwindled. After a 12-year exile from Apple, Jobs returned in 1997 to rescue and head the company. A year later, he introduced the iMac, a desktop computer with shapes and colors that departed from beige Windows boxes at the time.
Then came the iPod music player in 2001, the iPhone in 2007 and the iPad tablet in 2010. They weren't Macs, but shared the Mac's knack for ease of use. Elements such as tapping on icons to open apps have roots in the Mac. The popularity of these devices drove many Windows users to buy Macs.
In recent years, PCs have declined as consumers turn to mobile devices. Apple sold 16 million Macs in the fiscal year ending Sept. 28, down 10 percent from a year earlier. By contrast, iPhone sales grew 20 percent to 150 million and iPads by 22 percent to 71 million.
The Mac has aged to the point that it's starting to draw inspiration from iPhones and iPads. Several Mac apps have been refined to look and work more like mobile versions. Macs now have notifications and other features born on mobile devices. Windows computers, meanwhile, now emphasize tablets' touch-base interfaces.
Yet without the Mac, we may never have had the iPhone or the iPad, and phones might do little more than make calls and send email.
