The iMac was Apple's first major product release under CEO Steve Jobs following his return to the financially troubled company he co-founded.

The iMac's all-in-one design is based around a cathode-ray tube display; the G3 processor, components, and connectivity were all included in a single enclosure.

Apple's head of design Jony Ive and his team developed a teardrop-shaped, translucent plastic case that was a radical departure from the look of the company's previous computers.

Critical response to the iMac was mixed; journalists said the machine would be good for new computer users but bemoaned the lack of legacy technology, and said the separate mouse and keyboard were uncomfortable.

The original model was revised several times, improving the processor speed, the amount of random-access memory, hard drive space, and other capabilities.

The iMac is credited with saving Apple from financial ruin, and for turning personal computers from niche, technical products to mass-consumer fashion.

[12] He planned to reduce Apple's extensive and confusing computer offerings to four products: a laptop and desktop model each for professionals and consumers.

[14] Jobs initially wanted the new consumer desktop to be a network computer—a cheap, low-powered terminal without disk drives that would connect to Internet servers.

Ive's design team was given Jobs's specifications for the new product in September 1997: it should be a distinctive, all-in-one computer with a price of about $1,200, much lower than the $2,000 (equivalent to $3,700 in 2023) for current entry-level models.

While collaboratively developing sketches, designer Doug Satzger drew an ovoid drawing based on his earlier work on Thomson televisions.

[29][31] Jobs wagered USB would solve the problem of accessory makers abandoning the shrinking Mac market with its special connectors.

[36] TBWA spent a week developing other names; Segall's pick was "iMac"; it was short, it said the product was a Macintosh computer, and the i prefix suggested the internet.

[40] The computer was supported by a $100 million advertising campaign that stressed the iMac's ease of use, internet connectivity, and striking contrast from competitors' products.

Actor Jeff Goldblum narrated television advertisements that rhetorically asked if computer companies had been in "thinking jail" making only beige products.

[41] Other promotions included radio giveaways, midnight launch events, and "golden tickets" hidden in select iMacs that could be redeemed for a tour of an Apple factory.

[42] To make sure Apple was able to ship as many Macs as possible, operations executive Tim Cook prebooked $100 million in air freight.

The iMac DV Special Edition came in a new color named graphite, and shipped with more RAM and a 13 GB hard drive—the largest capacity in the line-up.

The most expensive model was the iMac DV Special Edition, which had a 500 MHz processor, 128 MB of RAM, a larger hard drive, and an exclusive snow color.

Apple supplemented the existing indigo and graphite colors with two new patterns, "Flower Power" and "Blue Dalmatian", which were intended as visual representations of music.

These models shipped with Mac OS X, 500, 600, or 700 MHz processors, up to 256 MB of RAM, and a 60 GB hard drive on the Special Edition.

[55] In comparison, Macworld's Andrew Gore said the iMac G3 might be as important as the original Macintosh in shifting the computing paradigm, and that Apple's "Think different" marketing campaign was not just empty talk.

[56] Reporters including Newsweek's Barbara Kantrowitz and the San Francisco Chronicle's David Einstein considered it the first promising step in Apple's possible resurgence.

[60] Many reviewers compared its curved look to the recently released Volkswagen New Beetle,[58][61] journalist Rob Morse likened it to a "huggable", futuristic machine like R2-D2 or a toy from The Jetsons.

[59] Positive reviews highlighted the computer's ease of use for setup and operation;[57][63][64] According to Morse, the iMac felt "almost human" and approachable for a non-tech consumer.

[69] Gore considered the loss of the floppy drive acceptable but wished that the CD-ROM module, which was identical to that of the PowerBook notebook, could be swapped.

[71] Other reviewers bemoaned the high cost of external replacements for the internal floppy disk drive,[72] low amount of installed memory,[60] and its tinny speakers.

[71] Another major complaint with the iMac was its original mouse and keyboard, which reviewers said were small and difficult to use comfortably,[73] calling them an example of style over substance.

[80] In the quarter the iMac shipped, Macintosh computer sales grew year-on-year for the first time since late 1995, and saw the Mac grow its worldwide market share from 3 to 5 percent.

[89][90] The iMac's sales helped buoy Apple while it released a modern operating system and refreshed the rest of the Mac lineup.

[92] Apple's consumer laptop the iBook followed the iMac's lead in a lack of legacy technology and use of colorful, translucent plastic.