Using MathReader
The Mathematica Notebook Reader

Mathematica  stores information in a kind of document called a "notebook".
The document you are now reading is itself a Mathematica  notebook.  You can read notebooks with MathReader, the Mathematica  notebook reader.

Mathematica  notebooks are usually divided into sections.  When you first open a notebook, you are usually shown only the headings for the sections.  MathReader  allows you to open up the sections to see the material inside them. To do this, simply double-click the angled bracket.

The rest of this notebook tells you more about notebooks and how to use MathReader.  To read the other sections of this notebook, open them by  double-clicking their brackets.

Notebooks and MathReader

Notebooks are a form of interactive document supported by Mathematica.
A notebook may contain text and graphics, together with Mathematica  input and output.  Notebooks can also include "movies": animated graphics created by Mathematica  or imported from other programs.

MathReader is a  program that allows you to look at and print Mathematica  notebooks.  With MathReader, you can read the text and  view the graphics and movies in any notebook produced by the X Windows, Macintosh, Microsoft Windows, or NEXTSTEP user interfaces for  Mathematica .

MathReader does not, however, allow you to create or edit notebooks, nor does it allow you to execute Mathematica  input.  To do these things you need a full copy of Mathematica.  Information on how to get one is given in the section below entitled  "Buying Mathematica ".

An important advantage of MathReader is that it is a relatively  small program, which runs on computers that do not have enough memory to run Mathematica..

You may give away copies of MathReader.  Please see the section "Distributing MathReader" for information on distribution policies.

The Structure of Notebooks

A Mathematica  notebook consists of a sequence of "cells", each of which can contain text, graphics, or Mathematica  input or output.  The extent of a cell is indicated by a bracket  on the right side of the window. 

The cells in a notebook are usually arranged in groups, which are analogous to the sections and chapters of a printed document.  The first cell of a group customarily contains a heading for the section of the notebook represented by that group.

The grouping is indicated by additional brackets on the right side of the window; the bracket for a group encloses the brackets of the cells in that group.  Sophisticated notebooks often contain several levels of hierarchical organization, indicated by several levels of brackets.

A group of cells may be open or closed.  When a group is open, all the cells in the group are displayed, but when it is closed only the first cell, which contains the group heading, is visible.  The presence of the remaining cells is indicated by a horizontal rectangle just inside the heading cell's bracket; the rectangle's width is proportional to the number of cells in the group.  In addition, the bracket of a closed group is angled at the bottom.

Highly structured Mathematica  notebooks are usually stored with all groups closed.  When you open such a notebook, you see just its group heading cells, which form an outline of the contents of the notebook.

You can open a closed group of cells by double-clicking the group's enclosing bracket (the one with an angle at the bottom).  When you have a group of cells open, you can close it again by double-clicking the bracket that spans the group.

Another way to open or close a group of cells is to select the group (by clicking its bracket) and then choose the Closed Group command in the Cell menu .  This command will open a closed group and close an open group.  If you want to open or close a group and all its subgroups at once, choose the Open All Subgroups or Close All Subgroups command, also in the Cell menu.

Animated Graphics

MathReader  allows you to view "movies" generated by Mathematica.  A movie is a sequence of frames displayed in quick succession.  Each frame in a Mathematica  movie is a graphics cell; a movie is a group of graphics cells.

There are two steps in viewing a movie: you select the movie you wish to see (a single notebook may contain several), and you give the command to begin the animation.

Selecting the Movie

To view a movie, you must first select it by clicking (once) the bracket that spans the group containing the frames of the movie.

Often the movie group will be closed, so that only the first frame is visible.  In this case the group's bracket has an angle at the bottom.  Simply click this bracket; you do not have to open the group to be able to see the movie.

You should be sure to click the correct bracket.  Clicking the innermost bracket would select only a single frame, and clicking a bracket too far to the right might select several movies at once.  Neither of these would produce the desired animation effect.

Animating the Movie

Once you have selected the group of cells that make up the movie, you can start the movie by double-clicking the first picture in the group.   (As an alternative, you can choose the Animate Selected Graphics command in the Graph menu.)  You can stop the movie by clicking anywhere inside the window.

Mathematica  shows a movie in the cell which contains the movie's first frame.  Movies in notebooks are often stored as closed groups, so that only this first cell is visible.

You can control the speed and direction of a Mathematica  movie as it runs by clicking the palette of buttons that will appear in the lower left corner of the window.  The first three buttons control the direction of the animation: backward, cyclically, and forward.  The middle button is a pause button. The two buttons to the right of the pause button make  the animation run slower and faster.  The rightmost button stops the animation.

Buying Mathematica

Mathematica for Multi-User  Systems

As of January 1994, Mathematica  is available for the following systems:

         DEC - Alpha OSF/1, RISC Ultrix and VAX/VMS (network license not available   for   VMS)
         HP Apollo - 680x0, RISC
         IBM - RISC System/6000
         MIPS - RISComputers and RISCstations
         NEC - EWS 4800
         NEXTSTEP -  Intel and Motorola-based compters
         Silicon Graphics - IRIS systems
         Sony -  NEWS RISC
         Sun - SunOS and Solaris for SPARC-based systems

         
Mathematica X Front End:    

The notebook user interface (front end) is included with versions of  Mathematica  for  DEC Ultrix, HP 700, IBM RISC System/6000, SGI, and Sun systems running the X Window  System.
    
Supercomputer Systems:

         CONVEX - C series 

Educational and student discounts are available. All specifications are subject to change without notice.

Mathematica  for the Macintosh

There are two versions of Mathematica  for Macintosh computers:

 Standard Version
 Enhanced Version

The Standard Version does not require floating-point hardware; it will run on any Macintosh which has sufficient RAM and disk space.  The Enhanced Version, which is optimized to do floating-point operations more quickly, requires a 68020 or higher CPU and takes advantage of a numeric coprocessor, when present.  The Enhanced Version also includes a separate binary for use with the Power Macintosh.

Note:  6MB application memory  required.  10 MB recommended. Mathematica  may use virtual memory, available under System 7.

Mathematica  for Microsoft Windows

Mathematica  for Windows requires:
          MS Windows 3.1 or later 
          MS-DOS Version 3.0 or later
          A 386-based or higher CPU
          Requires 4 MB of physical RAM plus
             8 MB or more of available swap space
          Requires 13 MB of available disk space for full installation 
          
Mathematica  for Windows supports all printers and graphics cards supported by Windows.

Mathematica  for Windows provides a notebook user interface, and supports sound with a sound card (e.g. SOUNDBLASTER), or under MS Windows 3.1.

Mathematica  for MS-DOS Systems

There are two versions of Mathematica  for MS-DOS systems:

Standard Version (386 or higher CPU required)
Enhanced Version (386 or higher CPU with numeric coprocessor required)

System Requirements:
          640 kilobytes regular memory and 4 megabytes extended memory
          12 megabytes hard disk space
          Additional 16 megabytes hard disk space recommended for virtual memory 
          
Supported video cards:
          CGA
          EGA
          VGA
          MCGA
          IBM 8514
          AT&T VDC 750
          Hercules graphics standards

Supported printers:
          HP LaserJet Series II and compatibles
          IBM Proprinter and compatibles
          IBM Quickwriter 5204 series and compatibles
          PostScript
          LaserJet
          Epson FX/LQ
          Toshiba P3 printers.

Mathematica  for MS-DOS provides DOS-style editing capabilities, but does not support the Mathematica  notebook interface.

Mathematica  for the NEC PC (9801 Series)

System requirements:
          640 kilobytes regular memory
          3 megabytes extended memory
          12 megabytes hard disk space
          Additional 16 megabytes hard disk space recommended for virtual memory
          MS-DOS version 3.0 or higher (version 5.0 or higher for the 9801RAS)
          Normal or high resolution display
          Numeric coprocessor (optional)
          
Supported printers:
          NEC PR series
          Epson P-code
          HP LaserJet Series II and compatibles
          IBM Proprinter and compatibles
          IBM Quickwriter 5204 series and compatibles
          PostScript
          Epson FX/LQ
          Toshiba P3 printers.

Mathematica  for the NEC PC provides DOS-style editing abilities, but does not support Mathematica  notebooks.

Mathematica  for the NEC PC includes Japanese language versions of Mathematica:  A System for Doing Mathematics by Computer  and Mathematica User's Guide.

Where to Get Mathematica

For information on these and other versions of Mathematica, visit your local software dealer, or contact Wolfram Research.

Wolfram Research, Inc. 
100 Trade Center Drive
Champaign, IL 61820-7237
USA
1-800-441-MATH (U.S., Canada)
217-398-0700 
fax: 217-398-0747
email: info@wri.com

European inquiries:

Wolfram Research Europe, Ltd.
10 Blenheim Office Park
Lower Road
Long Hanborough
Oxon OX8 2LN
UNITED KINGDOM
+44-(0)993-883400
fax: +44-(0)993-883800
email: info-euro@wri.com

Mathematica  Educational Grant Program

A Mathematica  Educational Grant Program is offered to educational institutions that want to improve the quality of their instruction through the use of Mathematica in the classroom and teaching laboratory.  The program is designed to help your school establish a teaching laboratory based on the Mathematica  system.

For information about the Educational Grant Program and Academic Site License Programs, contact the Wolfram Research Sales Department at 1-800-441-MATH or email info@wri.com.

In Europe, contact Wolfram Research Europe Ltd., +44-(0)993-883400

The Mathematica  Book

The main documentation for Mathematica Version 2  is the book Mathematica : A System for Doing Mathematics by Computer, Second Edition, by Stephen Wolfram, published by Addison-Wesley (1991).  The book is available at most bookstores.    

     Softcover version (ISBN 0-201-51507-5)
     Hardcover version (ISBN 0-201-51502-4)
     German version (ISBN 3-89319-371-5)
     Japanese version (ISBN 4-7952-9614-6)

To order the book directly, call Addison-Wesley at
     USA:  1-800-447-2226
     Japan:  81-3-3291-4581
     Germany (Bonn):  0228-985-150

The Mathematica Journal

Miller Freeman Publications publishes a quarterly periodical devoted to Mathematica-
related topics. For information about The Mathematica Journal, or to subscribe, contact:

The Mathematica Journal
Miller Freeman Publications
600 Harrison Street
San Francisco, CA  94107
(415) 905-2200
(415) 905-2234 (fax)

Mathematica  in Education

Mathematica  in Education  is published quarterly  by TELOS/Springer-Verlag.  It is devoted to topics related to the use of Mathematica  to enhance education. For information about  Mathematica  in Education, contact:

Mathematica  in Education
TELOS/Springer-Verlag
3600 Pruneridge Avenue, Suite 200
Santa Clara, CA  95051
USA

Mathematica World

Mathematica World  is an electronic magazine distributed on diskette and published monthly. It aims to encourage users to develop their skill and expand their use of Mathematica. For information about Mathematica World, contact:

Mathematica World
Ormond College
University of Melbourne
Parkville Vic 3052, Australia
Phone/Fax: 61-3-349-2001
email: mathematica@matilda.vut.edu.au

Recent Articles about Mathematica   Version 2

Reviews

IEEE Circuits and Devices: "Mathematica !," September 1993.

MacWorld: "Mathematica 2.2," September 1993.

Compute: "Mathematica," December 1992.

SunExpert: "Mathematica Version 2.0," May 1992.

PC Magazine: "Mathematica for Windows: Reshaping Math Software with Graphics and Sound," March 31, 1992.

Computer Shopper: "Figure It All Out with Mathematica 2.0," January 1992.

Product Comparison

Notices of the American Mathematical Society: "Maple V and Mathematica," October 1992.

PC Magazine: "Symbolic Math Software: It's Not Just for Mainframes Anymore," August 1992.

MacWorld: "Mathematica  Analysis," June 1992.

BYTE: "What You See is What You Solve: Mathematica and MathCAD for Windows," May 1992.

Applications

Scientific Computing and Automation: "Giving the Boot, Block and Shuffle to Statistics," March 1994.

Scientific Computing and Automation: "Applying Mathematics to Advanced Engineering Problems," July 1993.

Scientific Computing and Automation: "Using a Mathematical Windows Program to Study Shapes," April 1993.

R&D: "Math System Spurs Modeling," January 1993.

T.H.E. Journal: "Math Software Improves 'Drudgery to Insight' Ratio," November 1992.

Dr. Dobb's Journal: "The Design of the Mathematica Programming Language," April 1992.

The Scientist: "Symbol-Crunching Programs: Mainframe Analytical Power Reaches the Desktop," September 28, 1992.

Books about Mathematica

Here is a list of current and forthcoming books on Mathematica:

Tutorials/Reference

S. Wolfram: Mathematica:  A System for Doing Mathematics by Computer, Second Edition, ISBN 0-201-51502-4 (Addison-Wesley, 1991).

S. Wolfram: Mathematica Reference Guide, ISBN 0-201-51012-X (Addison-Wesley, 1992).

T. Gray and J. Glynn: The Beginner's Guide to Mathematica Version 2, ISBN 0-201-58221-X (Addison-Wesley, 1992).

N. Blachman: Mathematica: A Practical Approach, ISBN 0-13-563826-7 (Prentice-Hall, 1992).

N. Blachman: Mathematica: Quick Reference, Version 2, ISBN 0-201-62880-5 (Variable Symbols, Inc., 1992).

M. Abell and J. Braselton:  The Mathematica Handbook, ISBN 0-12-041535-6 (AP Professional, 1992).

W. Ellis and E. Lodi: A Tutorial Introduction to Mathematica, ISBN 0-534-15588-X (Brooks/Cole, 1991).

R. Maeder: The  Mathematica  Programmer,  ISBN 0-12-464990-4 (AP Professional/Academic Press, 1994).

R. Maeder: Programming in Mathematica, Second Edition, ISBN 0-201-54877-1 (Addison-Wesley, 1991).

A. Schuchat and F. Schultz: The Joy of Mathematica: A Point-and-Click Way to Use and Learn Mathematica,  ISBN 0-201-59145-6 (Addison-Wesley, 1994).

J. Gray: Mastering Mathematica: Programming Methods and Applications,  ISBN 0-12-296040-8 (Addison-Wesley, 1994).

Applications

A. Allen: Introduction to Computer  Performance Analysis with  Mathematica, ISBN 0-12-051070-7 (AP Professional/Academic Press, 1994).

J. Freeman: Simulating Neural Networks with Mathematica, ISBN 0-201-55629-X (Addison-Wesley, 1994).

I. Vardi: Computer Recreations in Mathematica, ISBN 0-201-52989-0 (Addison-Wesley, 1991).

T. Gray and J. Glynn: Exploring Mathematics with Mathematica,
ISBN 0-201-52809-6 (Addison-Wesley, 1991); includes CD-ROM.

L. Parker  and S. Christensen: MathTensor: A System for Doing Tensor Analysis by Computer,  ISBN 0-201-56990-6 (Addison-Wesley, 1994).

A. Riddle  and S. Dick: Applied Electronic Engineering with Mathematica,  ISBN 0-201-53477-0 (Addison-Wesley, 1994).

W. Shaw  and J. Tigg: Applied Mathematica: Getting Started, Getting It Done,  ISBN 0-201-54217-X (Addison-Wesley, 1994).

S. Skiena: Implementing Discrete Mathematics: Combinatorics and Graph Theory with Mathematica,  ISBN 0-201-50943-1 (Addison-Wesley, 1991).

S. Wagon: Mathematica in Action, ISBN 0-7167-2229-1 (W. H. Freeman, 1991).

R. Crandall: Mathematica for the Sciences, ISBN 0-201-51001-4 (Addison-Wesley, 1991).

M. Abell and J. Braselton: Mathematica by Example, Revised Edition, ISBN 0-12-041530-5 (AP Professional, 1994).

M. Abell and J. Braselton: Differential Equations with Mathematica,
ISBN 0-12-041538-0 (AP Professional, 1992).

D. Vvedensky: Partial Differential Equations with Mathematica, ISBN 0-201-54409-1 (Addison-Wesley, 1993).

H. Varian, ed.: Economic and Financial Modeling with Mathematica,
ISBN 0-387-97882-8 (TELOS/Springer-Verlag, 1993).

A. Gray: Modern Differential Geometry of Curves and Surfaces, ISBN 0-8493-7872-9 (CRC Press, 1993).

T. Wickham-Jones: Computer Graphics with Mathematica, ISBN 0-387-94047-2 (TELOS/Springer-Verlag, 1994).

R. Gaylord and P. Wellin: Computer Simulations with Mathematica: Explorations in the Physical and Biological Sciences, ISBN 0-387-94274-2 (TELOS/Springer-Verlag, 1994).

Textbooks/Courseware

V. Ostovic: Computer-aided Analysis of Electric Machines: A Mathematica Approach, ISBN 0-13-068859-2 (Prentice-Hall, 1994).

J. Robertson: Engineering Mathematics with Mathematica,  ISBN 0-07-053171-4 (McGraw-Hill, 1994).

J. Feagin: Quantum Methods with Mathematica, ISBN 0-387-97973-5 (TELOS/Springer-Verlag, 1994).

B. Davis, H. Porta, J. Uhl: Calculus&Mathematica, ISBN 0-201-58461-1 (Windows version); 0-201-58153-1 (Macintosh/NeXT version) (Addison-Wesley, 1994).

E. Packel and S. Wagon: Animating Calculus: Mathematica Notebooks for the Laboratory,  ISBN 0-7167-2428-6 (W. H. Freeman, 1994).

R. Gaylord, S. Kamin, P. Wellin: Introduction to Programming with Mathematica, ISBN 0-387-94048-0  (TELOS/Springer-Verlag, 1993).

P. Crooke and J. Ratcliffe: A Guidebook to Calculus with Mathematica, ISBN 0-534-15483-2 (Wadsworth Publishing, 1991).

D. Burbulla and C. Dodson: Self-Tutor for Computer Calculus Using Mathematica,
ISBN 0-13-803784-1 (Prentice-Hall Canada, 1992).

J. Finch and M. Lehmann: Exploring Calculus with Mathematica, ISBN 0-201-55572-7 (Addison-Wesley, 1992).

B. Braden, D. Krug, P. McCartney, S. Wilkinson: Discovering Calculus with Mathematica, ISBN 0-471-53969-4 (John Wiley & Sons, 1992).

M. Hoeft: Laboratories for Calculus I Using Mathematica, ISBN 0-201-54345-1 (Addison-Wesley, 1992).

K. Stroyan: Calculus Using Mathematica , ISBN 0-12-672976-X (Macintosh version); 0-12-672977-8 (DOS version);  0-12-672978-6 (NeXT version) (Academic Press, 1993).

A. Sparks, J. Davenport, and J. Braselton: Calculus Labs Using Mathematica,
ISBN 0-06-501196-1 (HarperCollins, 1993).

R. Skeel and J. Keiper: Elementary Numerical Computing with Mathematica,
ISBN 0-07-057820-6 (McGraw-Hill, 1993).

M. Kerkhove and V. Nall: Calculus Laboratories with Mathematica, Volumes 1, 2, & 3, ISBN 0-07-034220-2 (Vol. 1); 0-07-034252-0 (Vol. 2); 0-07-034253-9 (Vol. 3) (McGraw-Hill, 1993).

Additional Sources

Selected Tutorial Notes, ISBN 1-880083-07-8 (Wolfram Research, Inc., 1993).

Foreign Language Titles

G. Baumann:  Mathematica in der Theoretischen Physik, ISBN 3-540-56210-9 (Springer-Verlag, 1993) (in German).

W. Burkhardt:  Erste Schritte mit Mathematica, ISBN 3-540-56650-3 (Springer-Verlag, 1993) (in German).

E. Henrich and H. Janetzko:  Das Mathematica Arbeitsbuch, ISBN 3-528-06528-1 (Verlag Vieweg, 1993) (in German).

S. Kaufmann:  Mathematica als Werkzeug:  Eine Einfuehrung mit Anwendungsbeispielen, ISBN 3-7643-2832-0 (Birkhuser, 1992) (in German).

M. Kofler:  Mathematica:  Einfuehrung und Leitfaden fuer den Praktiker, ISBN 3-89319-485-1 (Addison-Wesley, 1993) (in German).

R. Maeder:  Informatik fuer  Mathematiker und Naturwissenschaftler: Eine Einfuehrung mit  Mathematica, ISBN 3-89319-519-X (Addison-Wesley, 1993) (in German).

E. Stelzer:  Mathematica:  Ein systematisches Lehrbuch mit Anwendungsbeispielen, ISBN 3-89319-495-9 (Addison-Wesley, 1993) (in German).

R. Schaper: Grafik mit Mathematica, ISBN 3-89319-612-9 (Addison-Wesley, 1994) (in German).

J. Kripfjanz and H. Perlt: Arbeiten mit Mathematica, ISBN 3-446-17649-7 (Hanser-Verlag, 1994) (in German).

G. Falco:  Mathematica: Principi e applicazioni, ISBN 88-7192-037-6 (Addison-Wesley, 1993) (in Italian).

Ryoji Moriya: Learning Mathematics with Mathematica: Introduction, ISBN 4-303-72780-6 (Kaibundo, 1993) (in Japanese).

Ryoji Moriya: Learning Mathematics with Mathematica: Linear Algebra, ISBN 4-303-72800-4 (Kaibundo, 1993) (in Japanese).

H. Ono: Mathematica: DSP and Control, ISBN 4-8101-8549-4 (Toppan, 1992) (in Japanese).

S. Kang, G. Nam, and G. Jun: Mathematica?!,  ISBN 89-315-4164-3 (Sungandang, 1993) (in Korean).

E. Castillo, A. Iglesias, J. Gutierrez, E. Alvarez, and A. Cobo:  Mathematica , ISBN 84-283-2017-9 (Editorial Paraninfo, 1993) (in Spanish).

J.P. Culioli:  Introduction a Mathematica, ISBN 2-7298-9144-7 (Ellipses, 1991) (in French).

A. Sfeir: Mathematica: Une Nouvelle Approche Du Calcul Scientifique, ISBN 2-87892-005-8 (Angkor Editeur, 1993) (in French).

Translations

Mathematica: Ein System fuer Mathematik auf dem Computer, Second Edition, ISBN 3-89319-371-5 (Addison-Wesley) (in German).

Mathematica in Aktion, ISBN 3-86025-041-8 (Spektrum Akademischer Verlag) (in German).

Mathematica griffbereit, Version 2, ISBN 3-528-06524-9 (Verlag Vieweg) (in German).

Guide d'initiation a  Mathematica 2, ISBN 2-87908-026-6 (Addison-Wesley) (in French).

Mathematica: Un Enfoque Practico, ISBN 84-344-0478-8 (Editorial Ariel) (in Spanish).

Mathematica: A System for Doing Mathematics By Computer, Second Edition,
ISBN 4-7952-9614-6 (Addison-Wesley, Toppan) (in Japanese).

The Beginner's Guide to Mathematics Version 2, ISBN 4-8101-8056-5 (Addison-Wesley, Toppan) (in Japanese).

Mathematica by Example, ISBN 4-938455-35-8 (Fuji Software) (in Japanese).

Self-Tutor for Computer Calculus Using Mathematica, ISBN 4-8101-8558-3 (Prentice-Hall, Toppan) (in Japanese).

Exploring Mathematics with Mathematica, ISBN 4-8101-8045-X (Addison-Wesley, Toppan) (in Japanese).

Computational Recreations in Mathematica, ISBN 4-8101-8038-7 (Addison-Wesley, Toppan) (in Japanese).

Mathematica for the Sciences, ISBN 4-8101-8036-0 (Prentice-Hall, Toppan) (in Japanese).

Programming in Mathematica, ISBN 4-8101-8043-3 (Addison-Wesley, Toppan) (in Japanese).

Implementing Discrete Mathematics: Combinatorics and Graph Theory with Mathematica, ISBN 4-8101-8050-6 (Addison-Wesley, Toppan) (in Japanese).

Mathematica: A Practical Approach, ISBN 4-8101-8538-9 (Prentice-Hall, Toppan) (in Japanese).

Partial Differential Equations with Mathematica , ISBN 4-8101-8069-7 (Addison-Wesley, Toppan) (in Japanese).

Mathematica in Action, ISBN 4-89242-143-X (Brain) (in Japanese).

Distributing MathReader

MathReader  is copyright © 1989-94 by Wolfram Research, Inc.
It is not "public domain".

Wolfram Research gives you permission to give away as many free  copies of MathReader  as you like, but you may not sell it, and you may not package it with other software that you do sell.  And you must include this file (Read This First!) with any copy of MathReader  you make.

If you give someone a copy of MathReader on a disk, then you may charge a fair price for the disk itself, and for such costs as duplication and inventory - this price should never exceed $5 per disk - but you must not charge for MathReader .  (If you obtained a Demonstration Notebooks Disk, which contains MathReader , directly from Wolfram Research, you probably paid such a fee.)

Here is an example: a Mathematica  User Group might keep a collection of notebooks in its library.  For a fee, a member of the User Group may obtain a copy of a notebook on disk.  The User Group may distribute MathReader on the same disks provided that the fee is not higher than what would cover its cost to produce and distribute the disks.  If a higher fee is charged, perhaps to reimburse the author of the notebook or to fund the User Group's activities, then MathReader must not be included on these disks (but it may be distributed by itself on other disks for which a lower fee is charged).

Another example: many schools, colleges, and universities have instructional computing labs where students have access to Macintosh computers.  A teacher who has Mathematica  might create course notes in the form of notebooks, intending students to use the school's computers to read the notes.  If the teacher does not charge for  course notes, the teacher may give the students disks containing MathReader and the course notes (the teacher may still charge for the cost of the disks).  If the teacher wants to charge for the course notes, she or he must distribute MathReader separately - perhaps just placing a copy in the computer lab, where the students may copy it onto their own disks for free.