I don't think if I copy a few pages in a book and take them home to read I am breaking the law. Are VCRs illegal? I can't get that material copied or distribute it, but I can record it.
As a technical trainer, I had to deal with copyright issues almost every working day and I sometimes think the intellectual property laws were written to keep intellectual property lawyers in business. Copying even a "few" pages may not be legal.
For example the copyright notice in my copy of
The New Oxford Annotated Bible, New Revised Standard Version with the Apocrypha states…
No part of this publication may be reproduced, stored in a retrieval system, or transmitted in any form or by any means, electronic, mechanical, photocopying, recording, or otherwise, without the permission of Oxford University Press. {emphasis mine}
Further down the copyright notice it says…
Up to five hundred (500) verses off the New Revised Standard Version (NRSV) may be quoted or reprinted without the express written permission of the publisher, provided that the verses quoted neither amount to a complete book of the Bible nor account for 50% or more of the written text of the total work in which the are recreated.
Not only can the rules be different for each specific document they are different for different kinds of material. The general rule for written material the limits you to copying ten pages of a published document that you
DO NOT OWN. That allows teachers to distribute a limited amount of material excerpted from copyright documents. However, the copyright holder may impose conditions that are either more or less strict.
No copies of sheet music are allowed without specific written permission of the copyright owner. (That cost a small church I know of a $10,000 fine because they were under the mistaken impression ASCAP would not come after a church making copies for the use of their choir.)
Performance material, such as VCRs, CDs,
etc. fall under a different category that permits a limited number of copies (I forget whether it is five or eight) "for [i]personal]/i] use" and may be given away so long as it is
free and there is no financial gain from the copies. Of course all of that is subject to individual copyright provisions granted by the copyright owner and specified in writing. It is that limit on the number of copies where music sharing services get into trouble.
Where software is involved, even Open Source, is tricky as different Open Source communities have different provisions allowing the use of the software and, in fact, developers often choose which open source license to operate under because of variations in the agreements.
So whether or not you can make legal copies of any copyright material requires you to read, and understand, the specific copyright notice for the specific item. And yes copyright owners can and will enforce their copyright. Otherwise they risk losing it and their source of income.