Aero Lite with Glass is a Windows 8 theme for Windows 7. You can install this theme on Windows 7 to get a Windows 8 like look and feel instantly.
Along with the Windows 8 like interface, the theme also implements Windows 9 like back and forward buttons in Windows Explorer. This is done by explorerframe.dll which is included in the theme folder.
The theme also includes Start ORB bitmaps, which puts Windows 8 Start ORB in Windows 7. Download Windows 8 Theme for Windows 7 and install this theme on Windows 7 to get a Windows 8 like look and feel.