This book contains the only complete and official listings for the disk File Manager System (FMS) commonly known as "Atari DOS 2.0S." You will note that we have clearly stated that the purchase of this book does not entitle you to make, sell, give, or otherwise distribute copies of either the original Atari DOS 2.0S or any modified version you may produce as a result of using this book.

By way of information, should you desire to produce and distribute a modified version of this product (e.g., to support a new disk drive), you must sign a contract and licensing agreement with the party who owns the rights to grant such licenses for non-exclusive uses. Currently, Optimized Systems Software is the only entity able to grant such licenses.

Some of you may find it strange that the publishers of COMPUTE! magazine are publishing this book. You might wonder why Atari, Inc. , hasn't released this information before. Why can you only obtain distribution rights from Optimized Systems Software? For the answers to these and other questions we present the following Introduction, an Inistorical perspective on the development of the systems software for the Atari Home Computers.