When assessing page structure and layout, there is a subtle way to use images to add marketing messages that don’t fit on the page.
Say for example that for your recruitment site you want to optimize a given page for the term “Accounting jobs”. Suppose that you also want to include a catchy marketing message such as “Exclusive opportunities in top international firms”, but have no way to put it in the text without it looking messy.
A way to solve this dilemma is to add the text under the “descriptive text” of the main image; this way the search engine still indexes the phrase. An added benefit: even though the marketing text is not visible to visitors straight away, they do see it when they hover over the text.