Aero Peek is one of the features of Windows 7 that allows users to quickly preview the contents of open windows without actually switching to them. It provides a convenient way to get a glimpse of what is happening in different windows without the need to navigate through them one by one.

Explanation:
When the mouse cursor is hovered over the bottom right corner of the taskbar, all open windows become transparent, except for the outlines. This action activates Aero Peek, which enables users to see through the windows and view the desktop or any gadgets that are displayed on it.

Benefits of Aero Peek:
1. Quick preview: Aero Peek provides a quick and efficient way to preview the contents of open windows without the need to switch between them. It allows users to stay focused on their current task while still being able to monitor other windows.

2. Enhanced productivity: By using Aero Peek, users can easily locate specific windows or applications they need without wasting time navigating through multiple open windows. This feature can significantly improve productivity, especially when working with numerous windows simultaneously.

3. Desktop customization: Aero Peek also allows users to customize their desktop by adding gadgets or widgets. With Aero Peek, they can easily view and interact with these desktop elements without minimizing or closing other windows.

How to use Aero Peek:
To use Aero Peek and make all open windows transparent, follow these steps:

1. Move the mouse cursor to the bottom right corner of the taskbar.
2. Hover over the small rectangular button located at the end of the taskbar.
3. All open windows will become transparent, except for their outlines.
4. To return to the previous view, simply move the mouse cursor away from the corner or click on any of the transparent windows.

Conclusion:
Aero Peek is a useful feature of Windows 7 that allows users to quickly preview the contents of open windows without switching to them. By making all windows transparent when the mouse is hovered over the bottom right corner of the taskbar, it enables users to get a glimpse of what is happening in different windows and provides a convenient way to view the desktop or any gadgets displayed on it. This feature enhances productivity and allows for easy desktop customization.