Copyright laws are intended to incentivise the creation of books, journals, art, music, software and other forms of creative expression. They give the author of a protected work certain exclusive rights, most notably the right to authorise copying and communication of their works to others. Because copyright typically exists for 70 years following the death of the author, much of the content that people interact with online is protected by copyright. This includes websites, social media services and the contents of online databases.
In order to get lawful access to copyright-protected material you must either have the permission of the copyright owner or rely on an exception to copyright as defined in the legislation (in the UK this is the Copyright, Designs and Patents Act 1988). In the UK there are a number of exceptions for accessibility which allow changes to be made to copyright-protected material without the copyright owner’s permission.
In the UK it is permissible to make accessible copies in certain circumstances. For more information see the CopyrightUser exceptions for disability page.