16 Aug 15 10:43 pm
Link blocks are simply block of links on a website, which are arranged in a column. Example of link blocks are your navigational menu that is found on your header, footer, within the page (category column, latest post menu, and the likes).
07 Jan 16 12:38 pm
Think of it as a way for Google to see that the sites that are linking to you are related. Like all on the same hosting server or something. If you have too many from the same C block it doesn't look natural.