This is the software publisher’s description.

Instant Eyedropper is a utility that will identify and automatically paste to the clipboard the colour code of any pixel on the screen with just a single mouse click.
Computing the colour code of an object on the screen is usually an involved, multi-step process: You press the Print Screen key to copy a screenshot to the clipboard, load a graphics-editing program, create a new file, paste the screenshot from the clipboard, zoom in on the object, use the "Pick Color" tool, and finally copy the HTML code of the colour to the clipboard.

Webmasters may repeat this operation many times a day. Just imagine how much time can be saved by using Instant Eyedropper to do the same thing with a single click.

Using Instant Eyedropper is easy. Simply move the mouse pointer to the Instant Eyedropper icon in the system tray. Press and hold the left mouse button and move the mouse pointer to the pixel whose colour you want to identify. That's it. The clipboard now contains the colour code - in HTML format (or any other format that you have previously specified). It can be pasted and used in any text or HTML editor or the Color Picker tool of Photoshop.