I will begin IE9 comparison with the user interface. Among the first things that people notice about any software or operating system is the user interface. Why do you think people hung to Windows Vista even though it was almost a mess? It was just because of the user interface. Coming to IE9 comparison (IE9 versus IE8), the most significant thing you will notice is the change in Internet Explorer’s user interface.

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The IE9 drops the multi bar system. It relieves itself from the traditional menu bar and places all important items on a single bar. This is to offer more canvas for websites as per
Microsoft, the software giant. In other words, placing all important things – the Address bar, the Tabs, and icons for Favorites, Home, and Tools – on a single bar offers more space for websites. It looks that Microsoft finally acknowledges that web browsers are meant for viewing the websites and not the design of web browser. Hence, it made the bookmarks bar, command bar, and even the status bar, optional.
This means that by default, you see only a single bar at the top where you can type in the URL or open new tabs. If you wish to go to a bookmarked URL, you can use the Favorites icon on the same bar. If you wish to see the status bar, or favorites bar, just right click at any empty space on the address bar and select the option in Internet Explorer context menu (see image).
The new tab page presents you with squares (thumbnails of pages that you surfed recently). It also offers an indicator on each square to show how frequently you used these websites: A strange but interesting method of presenting browsing history!
Tip: If at anytime, you feel the need for the traditional menu bar, press ALT key. This is a hidden shortcut that presents the traditional menu bar until you press ALT again or until you click on the webpage.