The bigger of the two was a sturdy youngster, very dark, with a mat of coarse hair on his head and coal black eyes.

    In the above sentence , the narrator described the hair and eyes of the boy in an effective way.

    The expression 'a mat of coarse hair' is a metaphor.

    A metaphor is a word / phrase used in an imaginative way to describe something or somebody in order to show that the two things have the same qualities and make the descriptions more effective.

    Now, hair of the boy can also be described as the hair of the boy is like a mat.

    A simile is a figure of speech that expresses the resemblance of one thing to another of a different category usually introduced by like, as… as.

    A simile, like a metaphor, is also a comparison.The primary difference is that a simile contains the words like, as, as….as to compare two things while a metaphor simply suggests different (dissimilar) things as the same(similar).

    Sunitha was an exceptional student. She was good at sports and other co-curricular activities too. One day the teachers were talking about her. The maths teacher said fondly, "My Sunitha is the Shakuntala of our school." The science teacher said, "She is as clever as Kalpana Chawla and as hard working as Marie Curie. One day she will bring the Nobel prize to our country." The physical education teacher started singing the praises of Sunitha saying, "You know, she runs like a hare and swims like a fish. And in the boxing ring? She is a leopard. I must say she is the Mary Kom of our state." Unlike other teachers, the social studies teacher hated this girl as Sunitha belonged to the so-called 'lower caste'. She said, "Sunitha... a hare, a fish and …what is that? … a leopard. She is more an animal than a girl, I suppose." All other teachers said in unison, "Yes, she is an animal for animals that cannot understand the metaphor in a language."