A 20th anniversary is a milestone worthy of celebration in its own right, but even more so when describing a computer. Few technology products boast such a feat in an industry where changing customer preference and exponential technical advancement can quickly obsolete even the most well-considered plans.

This Sunday, Apple’s iMac line joins the 20-year club. Its ticket to entry is two decades of valuable lessons and ideas that tell the recent history of the personal computer industry and reveal Apple’s priorities and values. The iMac’s timeline tells many stories – some of reinvention and business strategy, others of software and hardware.

Perhaps none are more significant than the iMac’s design story. Explorations of color, form, material, and miniaturization have marked significant breakthroughs throughout the years. On this anniversary week, we’ll take a look at the design evolution of the iMac.

Sorry, No Beige

In early 1998, a reinvigorated Apple was in the midst of filling out its new, four-quadrant product matrix. Next in line was a consumer-grade desktop computer, a segment of the market that had grown stale and uninspired. Beige towers still dominated the landscape, and even Apple’s own designs looked largely the same as they had for the past decade. Apple had the opportunity to make a splash, and they embraced it.

The original iMac was a product full of firsts. It was Apple’s first computer to be built for the internet era (that’s where the i comes from.) It was the first to drop all legacy I/O in favor of the more modern USB standard. And it was the first to show that computers could be cool. To design the iMac, Apple pushed its latent industrial design team, a group that had been underserved by previous company leaders. While the iMac wasn’t the first Apple product to use translucent plastic, it was decidedly more “Un-PC,” without a spot of beige to be found.

Then-VP of Industrial Design Jony Ive asked “What computer would The Jetsons have had?” when designing the original iMac. Retro-futurism played a quietly important role in the computer’s appeal to customers, which was reminiscent of both the aesthetic used in the animated cartoon series and even vintage computer terminals. The iMac’s vibrant hues also embodied the spirit of 1960s Olivetti typewriters, which were notable for their use of color in a market dominated by dull, corporate designs.

High-Technicolor

“Bondi blue” was the color chosen for the first iMac, allegedly named after the waters of Bondi Beach in Sydney, Australia. In early 1999, Steve Jobs announced a line of five new iMacs spanning a range of colors: blueberry, grape, tangerine, lime, and strawberry. Colors made the computer feel more human and let users express themselves. Even Apple’s pro products would later get a splash of color, like the iMac-inspired line of Studio Displays that debuted in 1999.

Engineering colorful, translucent Macs turned out to be no small task. According to Jobs, the plastics simply didn’t exist when Apple began their research. The company’s teams spent over 6 months determining how to produce the exact colors they wanted.

Playlist: Apple’s iMac color commercials.

Less than a year later, the iMac saw another major design change. Refined styling including a shorter case, improved speakers, and slot-loading optical drive smoothed out the computer’s rough edges. Apple miniaturized the internal components, making the new iMac fan-less and even more translucent. Ventilation was inconspicuously added around the computer’s handle for convection cooling. In addition to the five colors previously offered, a special edition iMac was available exclusively in a translucent shade of graphite.

Apple continued to experiment with the iMac’s colors in successive models. In 2000, 4 new colors – Indigo, Ruby, Sage, and Snow joined Graphite at various price points, replacing the 5 original colors. Also bundled with the iMac were Apple’s new Pro Keyboard and Mouse, the latter proving to be much more ergonomically popular with customers than the “hockey puck” mouse that shipped with the first iMacs.

All 13 of the G3-based iMac’s colors.

In early 2001, Ruby, Sage, and Snow made way for two new “colors” that Steve Jobs said were in the works for 18 months. Both “Flower Power” and “Blue Dalmatian” iMacs featured patterns molded directly into the plastic case, rather than being applied decals. In July of the same year, Snow returned and both patterns were dropped, leaving three colors in the line.

The Ultimate Digital Hub

At Macworld San Francisco in 2002, the iMac’s design conversation shifted from color to shape. A ground-up redesign was needed to facilitate the transition from CRT displays to flat panel, LCD technology. Apple chose not to “take a hacksaw to” the outgoing iMac, instead creating an entirely new form which Jony Ive remarked “appears to defy gravity.” A 15-inch LCD panel suspended on a polished neck was anchored by a domed base housing the iMac’s components. By keeping the computer’s chassis distinct from its display, the LCD panel could remain thin and “true to itself,” according to Steve Jobs.

The new design was a perfect example of how constraints can facilitate elegant solutions. Rather than waiting for component technology to catch up with their design ambitions, Apple turned the limitation into a feature. While objectively more modern looking than its predecessor, the new iMac still retained the charm of the original. Some have called it the “Luxo Lamp iMac,” referring to Pixar’s Luxo Jr., and others have drawn comparisons to the famous 1950s line of Philco Predicta televisions. Pixar even collaborated with Apple to make two animated shorts featuring the iMac. The computer’s radical design has today earned it a place in the Museum of Modern Art’s Architecture and Design department.

It’s worth noting that Apple’s innovative design wasn’t without compromise. All models of the iMac again included a fan. The computer also came bundled with Apple Pro Speakers, superior to the computer’s internal speaker, but at the expense of extra wires on your desk. 17 and 20-inch models of the iMac launched later in 2002 and 2003 stretched the limits of the visual balance achieved in the 15-inch model. And gone from this generation were slot-loading optical drives, a highlight of the previous generation. Again, Apple took advantage of the limitation by using the tray-loading drive to personify the computer. In a television ad, an iMac displayed in a store window mimics a pedestrian by sticking out its “tongue.”

From The Creators Of The iPod

Apple’s pitch for the next-generation of iMac was simple. “From the creators of the iPod.” One sentence succinctly spoke to how quickly Apple’s business had been transformed by the music player. Once a single-purpose accessory, the iPod was now an integral part of modern digital lifestyles, and directly influenced the design of Apple’s larger products.

At first glance, the iMac G5’s design appears to contradict comments Steve Jobs made while introducing the previous generation system less than three years prior. Tucked behind the display is the entire computer, with drives mounted parallel to the display. Even today, commenters point to the event as an example of Steve Jobs backtracking on his word. What’s more likely is that the technology needed to house an iMac in a relatively thin case without sacrificing performance had finally become available.

With a profile just under 2 inches deep and suspended on an aluminum pedestal, Apple claimed that the iMac G5 was the world’s thinnest desktop computer at the time. The company’s pro line of Cinema Displays announced earlier the same year shared a very similar design language and thickness to the new iMac, but were framed in aluminum to match the Power Mac G5. The iMac’s plastic case, in contrast, complemented Apple’s other consumer products like the iBook and iPod. Slot-loading drives returned, and a removable back panel made the system easily expandable and serviceable.

Where Did The Computer Go?

In October 2005, the iMac G5’s case was thinned out, with tapered edges and repositioned I/O along the back. Apple also integrated an iSight camera above the display – a first for any Mac. Previously, video conferencing required the purchase of Apple’s standalone iSight camera – a large, $150 accessory that connected with a FireWire cable. The updated iMac G5 also shipped with Apple’s new 6-button infrared remote, an accessory built to control Mac OS X’s Front Row media application, and later used with the first-generation Apple TV. When not in use, the remote magnetically attached to the side of the iMac.

The G5’s thinner design was only a few months old when Apple announced that iMacs would be the first Macs to ship with Intel processors. Overnight, a computer that was twice as fast fit inside the same case. A refresh in September 2006 added a 24-inch model to the lineup – the iMac’s largest display yet.

The All-In-One For Everyone

Just as the iPod had inspired the design of the iMac G5, the iPhone inspired Apple’s next generation desktop. A large, glossy display framed by a black glass bezel and aluminum housing made the iMac look instantly more modern. Plastic was banished almost entirely, save for a matte black rear panel. Matching ultra-thin aluminum keyboards completed the look. A single visible screw on the outer casing was used to access a RAM upgrade slot. Similar styling would make its way to Apple’s Cinema Display and unibody MacBooks.

In addition to complementing the iPhone, the move to an aluminum and glass enclosure offered several benefits for Apple. Steve Jobs noted that professional users felt the new design looked more like a pro computer than the outgoing model, and that consumers felt it looked even more like a high-end consumer product. The feedback may have contributed to Apple’s decision to favor aluminum and glass over white plastic on their consumer-grade MacBook in 2008.

Aluminum and glass are also highly recyclable. Apple’s tolerances for environmentally friendly design have grown continuously tighter, and the move to 20 and 24-inch displays meant that even more material would be used in every machine. Switching to aluminum and glass over plastic represented a big leap forward in sustainability.

For Your Viewing Pleasure

If aluminum and glass made the iMac look more like a pro product, it deserved to feel like one, too. Introduced in October 2009, the conversation around the 21.5 and 27-inch iMacs was dominated by displays. Widescreen, LED-backlit panels were suited for media consumption and creative applications. Increased chassis width also meant that more powerful internal components could be used.

While displays were the largest change, Apple tweaked the iMac’s design in several other ways as well. Edge-to-edge glass and a full aluminum back created a more seamless appearance. A wireless keyboard and new Magic Mouse came standard, replacing the Mighty Mouse and wired Apple Keyboard with Numeric Keypad. A remote for controlling Front Row was no longer included in the box.

Taken Right To The Edge

A determination to make the iMac even thinner drove Apple to develop and refine new and existing engineering processes for 2012’s models. A laminated panel coated by a process called plasma deposition made the display thinner and 75% less reflective. The computer’s aluminum case had edges too thin to easily weld using traditional methods, so Apple turned to a process called friction-stir welding, more commonly used in the construction of aircraft parts. These and other advancements led to a 40% reduction of the computer’s internal volume. Tapering down to a thickness of just 5mm, the new iMac still bulged in the center, but hid it well. “Isn’t it amazing how something new makes the previous thing instantly look old?” Marketing SVP Phil Schiller commented during 2012’s reveal.

As the iMac’s design victories increasingly took the form of internal architecture innovations, Apple found themselves faced with another limitation – the slow, spinning hard drive. While the thin iMacs followed in the footsteps of the MacBook line and dropped their optical drives, solid state storage was still too expensive at high capacities to justify as the only option. Apple’s solution was the Fusion Drive, a hybrid storage option that combined the performance of a solid state drive with the capacity of a traditional hard drive by fusing two separate volumes together in software.

While the Fusion Drive was a clever solution to a technical problem, just like the first flat panel iMac, it was born from constraints. Component costs continue to drop, but only when flash storage can closely compete on price with spinning hard drives will the iMac be able to embrace a totally solid state future.

14.7 Million Pixels

The 2012 MacBook Pro was the first Mac to offer a Retina display, a high pixel density display technology first used in iPhones and iPads. By 2014, Apple was ready to bring the Retina display to the iMac. Arriving first on the 27-inch model and later on the 21.5-inch, 5K and 4K panels again provided a tough internal design challenge. Apple says they had to rethink every component in the iMac to support such high resolutions. To drive 14.7 million pixels, a custom display timing controller (TCON) had to be built from scratch, since none existed.

A spec bump in 2015 introduced new versions of Apple’s Magic Mouse and Trackpad, as well as a new Magic Keyboard. All three accessories are powered by rechargeable, rather than AA batteries, in an effort to eliminate waste. In 2017, even brighter and more color-accurate Retina displays were added.

Power To The Pro

It would be remiss not to acknowledge how much the desktop computer market had changed by 2017. The first iMac was designed to combine the excitement of the internet with the simplicity of the Mac. A wide library of software titles and easy setup made it an ideal system for computer users of all skill levels. In many ways, today’s iPads philosophically embrace the same ideals.

iMacs, on the other hand, were increasingly being employed by pro customers. High resolution displays, steadily more powerful hardware, and Thunderbolt connectivity made them ideal systems for creative professionals. Yet, pro users were growing worried about Apple’s long-term commitment to powerful desktop hardware. At last year’s WWDC, Apple quelled the fears of the pro market by introducing the iMac Pro.

The new desktop system sailed into uncharted territory for the iMac. Unlike the Special Edition G3-based iMacs of years past, the iMac Pro wasn’t just a more powerful model, it was completely re-engineered. Housed in the 5K iMac’s thin aluminum enclosure, a new space gray finish makes it obvious at a glance that you’re not looking at a normal configuration.

The evolution of the iMac’s internal architecture.

A new ventilation system on the rear of the computer is the next indication of the iMac Pro’s power. In order to drive workstation-class performance in such a tight space, equally powerful cooling was necessary. The iMac Pro’s internal design story begins with dual centrifugal fan systems resembling the horns of a ram, placed side-by-side in the heart of the computer. Large air channels allow heat to dissipate efficiently and quietly. With such striking internal architecture, the iMac Pro feels even more deserving than the original iMac of the translucent housing used to show off the computer’s components.

Apart from the 5K display, the iMac Pro shares few parts with its silver sibling. It’s the first Mac to offer up to an 18-core CPU. It’s also the first to use the T2 chip, custom silicon that controls critical system tasks and offers benefits like improved data encryption and a secure boot process.

The Vision Is Brighter Than Ever

Placed side-by-side with today’s models, the original Bondi blue iMac is nearly unrecognizable as a member of the same family. Yet, the iMac’s lineage follows one unbroken thread over the past two decades. Apple’s goal to make a powerful, easy to use all-in-one has not wavered. Perhaps Jony Ive summed it up most succinctly when he said Apple’s approach was to “evolve a solution until it seems completely inevitable, completely essential.”

The iMac’s design story is one of endless evolution, proof that innovation is the result of unrelenting iteration.