As shown in the video from the left (or click here), you can use this images to install Chrome OS on your device.
Make sure that your CPU is compatibe with Chrome OS and (if it is) download the matching Chrome OS recovery image from below. You can watch this video to learn how to find out if your CPU is compatible with Chrome OS, and if it is, which recovery image you need. For more details see the Chrome OS Page.
You can use this images for full installation or for making a Chrome OS dual boot system with Windows. All you need is a minimum 16GB USB drive and Rufus.