When you install Firefox it will automatically ask you is you would like to import favorites/bookmarks from other browsers, including Internet Explorer. That certainly does make the transition easier.
One note, though: Later, if you save a favorite in IE it will not automatically be added to your Firefox bookmarks or vice versa. There are third-party extensions that can sync your bookmarks between browsers on a regular basis for those that switch back and forth, but it's not a standard feature yet.
Hope this helps,
John
Sorry if this sounds elementry, but when changing from IE, do I have to start all over with all my bookmarks or can they be transferred? Thanks

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