We know what it means to get all up in our grill, but how does someone get all up in our grid?  We've always wondered about that random assortment of friends that pops up on the left hand side of our Facebook profile. Well, turns out they're not so random after all, but rather are specifically selected by Facebook (although they're still not as cut-throat as Bebo's top 16.) The social network actually employs a special algorithm designed to keep you interacting with long lost pals. This explains why people you haven't interacted with since school often appear on the list - and we thought it was because they were secretly stalking us. Facebook have said that the people you see in your top nine grid are a "group of relevant friends intended to be a useful prompt." The folk at Motherboard investigated further and explained: "In other words, these are the people the algorithm is subtly encouraging you to interact with. Or if someone else is visiting your Facebook page, it’s a sampling of people that person might want to connect with based on your mutual friends or interests." "So the random high school acquaintance that’s been popping up in your highlighted friends could be the algorithm gently nudging you to keep in touch with someone you’ve been friends with a long time. "On the flip side, it may show you people you recently friended to jumpstart the connection, even if you haven’t interacted yet. The formula also gives extra weight to people who recently posted stories or photos. Why does Facebook care if we interact with long lost pals? Well, according to the Irish Mirror, their advertisement-based business model works best when we interact with as many people as possible. We feel more like pawns in a chess game every day. Feature image courtesy of Motherboard.