The power of a visual image is determined by a complex array of elements. Anyone who creates a page for a magazine, makes a PowerPoint presentation, designs a brochure, prepares a poster or dreams up an idea for an infographic is faced with some important questions:

* Why is it better to put this photo here rather than there?

* What background color should I use for my presentation?

* What do I need to bear in mind when creating an internet page?

* Is it better to use a table, a graph or an i...