Code page should be semantic, to be friendly to search engines.
First of all, remember that websites are created for the people and must be so constructed that the reader understand the information contained in it.
The first visiting our web site are robots. Such robots to index the content of our website, so that it is accessible to search engines. However, do not have the ability to classify the information contained therein. The only thing they see is a set of words in a string without the mutual relations of which using special algorithms compare our text with the data in its database. Please also note that the information in graphic form will be completely inaccessible to the robot.
Only man is able to classify read information and evaluate their suitability. To our side has been understood by the software processing network resources, should include semantic code (suitable placement HTML tags in your code).