How can memes be engineered to carry political messages? A team at University College, London, has found that some far-right websites and message boards have a disproportionate impact on the memes that spread on mainstream social networks. The astronomer Carl Sagan famously said that there were more stars in our Universe than grains of sand on the Earth’s beaches. But was it actually true? We try to count the nearly uncountable. Dividing people into groups is part of our social experience: we build our identities through groups we belong to, and these identities can be numerous and elastic, but what makes us decide who is like us and who is the other? Sandra Kanthal reports. (Photo: One example of the “Distracted Boyfriend” meme. Credit: Getty/iStock/BBC)