Oriki: What is the importance of chanting Oriki to the Orisa and IFA?

Ori kiki: What does it do?

Does Oriki follow a pattern or formula like Odu? Does oriki give information seperate from Odu or does Oriki use information from Odu? Translation of what Oriki means? The picture below is of women chanting Oriki of a town at the installation of a new Oba. Thank you to all who answer.