A small, plump, brown and grey bird with black markings, that has a short, strong bill. Most are social, occurring in flocks, and several species live close to human dwellings, making them one of the most familiar birds. They are omnivorous, feeding on insects while breeding and on seeds the rest of the year. True sparrows form the family Passeridae, with 11 genera of 40 species, native to Eurasia and Africa but introduced so widely that they have an almost worldwide distribution.