PDF files – should they be contained in the images folder... or not?

[MBKrebs]

I have googled this question in just about every form possible and I can't find an answer. Are .pdf files considered images, and stored in the images folder? Or are there fewer issues by locating them in the site root folder? I don't want to sound like an absolute newb, but this is one of those questions that just lingers...

[Jon Fritz]

PDFs are not images (typically)...

The vast majority of PDFs are not simple images, like a jpeg or a gif. They can be a pretty rich file format, with interactivity, embedded fonts, as well as images. They can have searchable text, and could have pretty much an entire website's content baked in for offline viewing.

Does that mean you need to have a "pdf" folder?

No, not at all. It's completely up to you how you want to organize your site. Aside from special cases, like using DW's Template or Library feature, there's no rule in DW saying you must separate all images from video, or pdfs from images via your directory structure. In fact, if your site's not all that big, using one folder for all non-html assets called "assets" and storing everything there would/could be just fine.
 
It's all up to the person/people putting it all together. Use as many or as few folders as makes sense to you.

Personally, I keep images and PDFs in their own folders, I also separate out pages by main sections into their own folders, but the choice to do so is yours.

One mans "organized" is anothers "directory structure of doom".

[BenPleysier]

I second @Jon Fritz in that there are no fixed rules on where to store asset files. My usual way, even for small websites,

assets
    images
    pdfs

[L e n a]

One mans "organized" is anothers "directory structure of doom".

By @Jon Fritz

To pick up on what @Jon Fritz says, in fact it's all so much a matter of context, of organization, and what is today may not be tomorrow...

Look, in most cases we operate as @BenPleysier demonstrates, it that is to say an assets folder, which divides the various types of media into sub-folders

And yet, in one of the last projects we were involved in, it concerns an industrial service provider which works on the renovation of pipes, and asbestos removal from premises, and for this it must present dozens and dozens of case studies, each case study presents carousels of images, images of procedures, XLS work and preparation documents, PDFs (specifications, procedures, brochures), etc... so for this type of project we have folders by project which themselves group together all types of media, including specific HTML pages, their particularities come from the naming convention used for the resources. .. but at least there is no excessive tree structure formalism, not having to create specific sub-folders for each media type each time, and for all that, each project remains easily exportable independently.

In every context, we have to opt for the most flexible and appropriate organization of our assets. There are no immutable rules.

[Nancy OShea]

PDF are media files (interactive forms, e-books, portfolios, video, audio, etc...). 

They require a special viewer like Acrobat or Free Acrobat Reader to view & interact with them.

I typically put PDF into a dedicated PDF folder, separate from web images and HTML files.