A book illustrator is a professional that creates drawings and other illustrations for books. The images that illustrators add help convey the ideas and messages of the books, as well as help, bring the stories alive. When illustrators trust their ability to surprise and be surprised, it can work wonders. And that’s what illustrations are supposed to do: shed a little light on the world in which we live in that might be unconventional.

“I am trying to tell a simple story in an interesting way. Don’t make things up. Looks at the world around you and draw it. Each drawing you do will contain the memory of your last drawing. That is what separates illustrators from art directors, designers and photographers. You are not a co-worker. You are a collaborator. This is an important distinction.” - Marshall Arisman

Today, a book illustrator can cover almost every area of practice that falls into illustration. It became a liquid term due to the trends shifting in favour of digital art with hand-crafted elements.
Illustrated books can be found everywhere. Of course, you’ll find more refined illustrations aimed at adult audiences mostly in specialised bookstores, while places like supermarkets usually have illustrated books in the children’s section. I believe that illustration today suffers the same fate as animation, having a common misconception that its target audience is children because serious mature adults don’t need silly pictures, blocks of text are enough.
But in reality illustrated books have been enjoyed by every age category for centuries, this is due to illustrations greatly widening the comprehension of the text and giving the book two dimensions, each supplementing the other and is not only for visual stimulation for kids.
WHSmiths Farnham
Waterstones Farnham
Sainsbury's Farnham
Oxfam book store Farnham
For this research I wanted to visit different bookstore to see how many illustrated books I could find and sadly most of them offered picture books meant for kids, no illustrated books or graphic novels dominated by Japanese manga's. I came to the conclusions that it might also be due to Farnham being relatively small town and illustrated books for adults a rarity so I wouldn't find stuff like that in here, because what I recall from visiting bookstore in Lithuania, they had a lot of graphic novels aimed at a wide audience.