Copyright on Internet Images and Text
The situation relating to copyright on the internet is confusing. The detail of laws in different parts of the world is different and as a result the issue is confusing to most people.
So, for example, the ‘socialmediaexaminer.com’,  which is an American page, says the following:
Copyright laws were established not to give the author the right to deny their work to other people, but instead to encourage its creation.
Article I, Section 8, clause 8, of the United States Constitution states the purpose of copyright laws is “to promote the Progress of Science and useful Arts, by securing for limited times to Authors and Inventors the exclusive Right to their respective Writings and Discoveries.”
It’s a delicate balance between the rights of the creator and the public’s interest. When in conflict, the balance tips more heavily toward the public’s interest, which is often contrary to what the creator believes to be fair or just. 
However, The UK government  says:
Sometimes permission is not required from the copyright-holder to copy an image, such as if the copyright has expired. Permission is also not required if the image is used for specific acts permitted by law (“permitted acts”, or sometimes referred to as “exceptions to copyright”).
People can use copyright works without permission from the copyright owner, such as for private study or non-commercial research, although some exceptions are not available for photographs. Further details are available here:
If permission is required to use an image, permission will need to be obtained from all the copyright owners, whether it is a single image with numerous creators, a licensed image, or an image with embedded copyright works. Sometimes there will be one person or organisation that can authorise permission for all the rights in that image; in other cases separate permission may be needed from several individual rights owners.
The creator of a copyright work such as an image will usually have right to be acknowledged when their work has been used, provided they have asserted this right. If you are unsure whether or not the creator has asserted this right, then it is recommended that you provide a sufficient acknowledgement when using their work. 
The key question for many of us who write blogs and who both quote from other sources and make use of pictures from those sources, is what is meant by the words in bold italics above.
1. Text on the Internet and in other primary sources
The first question to address is what is meant by ‘fair dealing’. Another government website  talks about ‘fair dealing’:
Certain exceptions only apply if the use of the work is a ‘fair dealing’. For example, the exceptions relating to research and private study, criticism or review, or news reporting.
‘Fair dealing’ is a legal term used to establish whether a use of copyright material is lawful or whether it infringes copyright. There is no statutory definition of fair dealing – it will always be a matter of fact, degree and impression in each case. The question to be asked is: how would a fair-minded and honest person have dealt with the work?
Factors that have been identified by the courts as relevant in determining whether a particular dealing with a work is fair include:
- does using the work affect the market for the original work? If a use of a work acts as a substitute for it, causing the owner to lose revenue, then it is not likely to be fair
- is the amount of the work taken reasonable and appropriate? Was it necessary to use the amount that was taken? Usually only part of a work may be used.
The relative importance of any one factor will vary according to the case in hand and the type of dealing in question. 
‘Fair dealing’ is one element of this issue. A more critical question is: What is meant by ‘Non-commercial research‘? One place to look for answers is with Wikipedia (Creative Commons) and specifically their comments relating to this matter. 
Non-Commercial (NC) “means not primarily intended for or directed towards commercial advantage or monetary compensation. The definition is intent-based and intentionally flexible in recognition of the many possible factual situations and business models that may exist now or develop later. Clear-cut rules exist even though there may be gray areas, and debates have ensued over its interpretation. In practice, the number of actual conflicts between licensors and licensees over its meaning appear to be few.” 
However, this site, which makes images widely available on the internet and specifies the licence on each item, is an American website and so governed by US Law rather than EU law. A while back I joined the ‘Copyright Aid’ forum so as to be able to check whether particular activity on my blog met the requirements of the law. My usual practice in relation to images is to ask the photographer or copyright-holder for permission to use the image. There are however circumstances when this is unnecessary or it is impossible. Under these circumstances two matters are important, first, a commitment to ‘fair-dealing’ as discussed above. And second, the status of any blog as a non-commercial activity.
Before turning to the advice provided Copyright Aid, here are the comments about these issues carried by the Jisc in the UK (formerly the Joint Information Systems Committee) whose role is to support post-16 and higher education, and research, by providing relevant and useful advice, digital resources and network and technology services.  Their website comments as follows (the emphasis is mine):
Fair dealing for research and private study (s.29 CDPA)
UK copyright law permits fair dealing with a work for the purposes of non‑commercial research and private study. This covers copying of all types of copyright work. It means that researchers and students can copy extracts from sound recordings, films and broadcast as well as literary, dramatic and musical works for these purposes.
The word ‘research’ is not defined but in terms of Section 29 of the Copyright, Designs and Patents Act 1988 (CDPA) means any form of research as long as its purpose is non-commercial.
The law requires that acknowledgement be given to the copied source when used in research or private study. For academic staff and research students, this creates the obligation to use proper citations. The only exception may be situations where acknowledgement would be impossible for practical reasons. 
It would seem therefore, that any blog or website which does not have a primarily commercial interest is free to quote directly from source material provided that the source is properly acknowledged. The Copyright Aid website  provided the following advice. If you follow the topic through you will note that I have specifically asked for permission to share this advice in this blog:
“UK copyright law is largely based on EU law on the subject, and by and large the EU takes a stance which is strongly protective of the rights of authors and creators. The phrase “provide[s] a high level of protection for rightsholders” appears in the preamble to all the main EU Directives concerning copyright and this is reflected in the judgments and opinions of the Court of Justice of the European Union (CJEU) when it is asked to clarify or interpret EU law; and currently the UK courts must follow the CJEU decisions. Other recitals in the Directives strongly assert the general desirability for rightsholders to be given fair remuneration for the use of their work, even though that use may itself be non-commercial in nature. For example the UK is unable to adopt one particular fair dealing exception permitted under the EU Directives which would allow individuals to make copies for private use of legally owned copyright works, such as music, in order that they may be played across a number of devices, for instance like ipods. This is because the UK has not put in place a satisfactory regime which ensures that the rightsholders are remunerated each time this copying occurs (see section 28B of the Copyright Designs and Patents Act 1988 which is currently not in force)
EU law tends to use the term ‘directly or indirectly commercial’ in this context, by which they mean that if your blog attracts ad revenue or sponsorship (eg via Patreon etc) then that would be classed as indirectly commercial. If you were to use an image in order to sell something shown in the image then that would be direct commercial usage. However if your use of an image or text is solely there to provide the basis for review of or discussion on a subject to which the image or text directly relate, then the balance shifts in your favour provided that you do not use more of the copyright work than is strictly justified by the blog posting itself.” 
Copyright Aid makes it very clear that the use of a single page from a document to illustrate a point being made in a blog is ‘fair-dealing’ provided it is there to illustrate what is being said/argued in the blog and that the source is properly acknowledged. In addition the blog should be neither directly or in-directly commercial.
2. Images on the Internet
Advice by ArtUK, on their website , considers issues relating to all artwork including photographs:
The concept of fair usage exists within UK copyright law, commonly referred to as fair dealing. It’s a framework designed to allow the lawful use or reproduction of work without having to seek permission from the copyright owner(s) or creator(s) or infringing their interest. In the UK, there are a number of ‘fair dealing’ exceptions to copyright law.
Images … can be used for non-commercial research or private study purposes, and other UK exceptions to copyright permitted to users based in the United Kingdom under the Copyright, Designs and Patents Act 1988, as amended and revised.
If you reuse an image, it is your responsibility to make sure that a copyright exception applies (such as fair dealing criticism and review, quotation, or reporting a current event).
If an image is released under a Creative Commons (CC) licence, other rules may apply and the type of CC licence is normally more permissive. Review ‘How you can use this image’ section on the individual artwork page to see what is permitted by a rights holder. 
The non-commercial fair dealing exception is allowed if:
1) The purpose of the use is non-commercial research and/or private study
2) The use of the materials is fair
3) The use is made by researchers or students for their own use only
4) Researchers give credit to the copyright holder
Generally, non-commercial use could be:
- Use in free educational lectures and classes
- Use on an individual or group’s website discussing the artwork in question
- Use on websites that are primarily information-led, research-oriented and obviously non-commercial in nature. 
Copyright Aid  has something interesting to add here, which they do as an aside in their advice. As they say, the matter below seems counter-intuitive but it is already confirmed by EU case-law.
Under EU law as interpreted by the CJEU, if you only link to an image, video or text which is hosted on someone else’s server and do not copy the work onto the server which hosts your blog, then you do not infringe copyright, and the fair dealing exceptions are irrevalent. What’s more you don’t have to be certain that the site hosting the image etc is doing so legally. This may seem counter-intuitive, but the CJEU analyses the issue from the perspective of those to whom the rightsholder had intended to allow access to his/her work in the first place. If, say, a photographer places an image for which he owns the copyright on his own website or on a site like Flickr without any technical barriers as to who may view the image, then the public which he/she has authorised to view the work is, potentially, anyone with internet access. Therefore if you link to that site in a way that a reader of your blog is served the image directly from the source server, you have have not infringed upon the right of reproduction or the right of distribution which belong to the copyright owner. You can even use framing techniques which make the image appear on your blog; the one thing you may not do under those circumstances is create a new copy which resides on the server which holds your blog. For that you need to rely on far dealing. 
Copyright Aid go on to summarise their advice:
So to summarise, the exceptions which may allow you to copy an image or text which is protected by copyright (see sections 28 – 31 CPDA) are based on the doctrine of fair dealing. This means that the use must be justifiable in the circumstances where the work is re-used and no more of the original work is used than the occasion demands. In two specific cases (section 29 private study/research, and section 29A data analysis) the use must be neither directly nor indirectly commercial. Fair dealing for the purposes of criticism, review, caricature/parody, quotation or news reporting may be commercial in nature, but must be accompanied by sufficient acknowledgement of the source. Note that (contrary to what the ArtUK article implies), photographs may not be used under the news reporting fair dealing exception. If you re-use an image or text which has been released under a Creative Commons or similar licence, ensure that you fully abide by the terms of that licence, for example if an attribution is required. 
It seems therefore that for artwork, photographs and text three dominant factors apply under EU law. They are:
- is the use fair;
- is it non-commercial; and
- is it a research-based use.
However, in addition, an image may appear on a blog even if no specific authorisation is provided by the copyright-holder provided a hyperlink is used rather than ‘copy and paste’.
- https://www.socialmediaexaminer.com/copyright-fair-use-and-how-it-works-for-online-images, accessed on 15th December 2019.
- https://assets.publishing.service.gov.uk/government/uploads/system/uploads/attachment_data/file/481194/c-notice-201401.pdf, accessed on 15th December 2019.
- http://www.gov.uk/guidance/exceptions-to-copyright, accessed on 15th December 2019
- https://wiki.creativecommons.org/wiki/NonCommercial_interpretation, accessed on 15th December 2019.
- This conclusion is borne out by the “Defining Noncommercial Study,” https://wiki.creativecommons.org/wiki/Defining_Noncommercial, accessed on 15th December 2019.
- https://www.jisc.ac.uk/guides/copyright-law/exceptions-to-infringement-of-copyright, accessed on 15th December 2019.
- https://artuk.org/about/copyright-exceptions#, accessed on 15th December 2019.
- https://www.copyrightaid.co.uk/forum/viewtopic.php?f=2&t=2788&p=8043#p8043, accessed on 15th and 16th December 2019.
- https://artuk.org/about/what-is-non-commercial-use-vs-commercial-use, accessed on 15th December 2019.