Google announced ChromeOS in July 2009 as a lightweight Linux-based system designed for web apps.
In early 2010, several "OEM Beta" or "Cherry" builds circulated on file-sharing sites and forums. These used a versioning scheme (like 1.0.x) that preceded the official Google Chrome OS release on the CR-48 prototype in late 2010. Technical Breakdown of the Name Google Chrome OS Linux i686 1.0.628 OEM Beta x86
To understand why Google targeted i686, you must remember the market in 2009. The "Netbook" craze was at its peak. Devices like the ASUS Eee PC, Acer Aspire One, and HP Mini ran Intel Atom processors—specifically the N270 and N280. Google announced ChromeOS in July 2009 as a