The advent of the internet and social networks has revolutionised the information space and changed the way in which we communicate and get informed. On the internet, a huge amount of information competes for our (limited) attention. Moreover, despite the increasing quantity of contents, quality may be poor, making the environment particularly florid for misinformation spreading. In such a context, our cognitive biases emerge, first and foremost, confirmation bias, i.e. the human tendency to look for information that is already in agreement with one's system of beliefs. To shade light on the phenomenon, we present a collection of works investigating how information gets consumed and shapes communities on Facebook. We find that confirmation bias plays a crucial role in content selection and diffusion, and we provide empirical evidence of the existence of echo chambers, i.e. well separated and polarised groups of like‐minded users sharing a same narrative. Immersed in these bubbles, users keep framing and reinforcing their world view, ignoring information dissenting from their preferred narrative. In this scenario, corrections in the form of fact‐checking or debunking attempts seem to fail and have instead a backfire effect. To contrast misinformation, smoothing polarisation is so essential, and may require the design of tailored counter‐narratives and appropriate communication strategies, particularly for sensitive topics.