I knew my love for Apple products wasn't just being a fanboy, the iMac and I share the same birthday. On August 15th, 1998 the 1st iMac went on sale.
The specs were a 15" CRT monitor, 4 GB hard drive (iPod nano sized), 233 MHz PPC G3 processor, 32 MB OF RAM, 56 kbps modem, CD-ROM drive, Mac OS 8.1, and weighed 40 pounds. The iMac will go down in history as the rebirth of Apple. Below is the 1st commercial for the 1st iMac.
Gizmodo has psoted a great visual history of the iMac showing TV ads for each iMac.