Footers can be found at the bottom of almost every web page, and often take many forms, depending on the type of content on a website. Regardless of the form they take, their presence is critical (and highly underrated).
Each UI generation often takes two steps forward, then one step back. Even as new technologies emerge (e.g., Artificial Intelligence (AI) and speech recognition), knowing established UX guidelines will help you avoid missteps. This was Jakob Nielsen's keynote at the UX Conference in Copenhagen.