title: Grep {n} The preceding item is matched exactly n times, is not clear to me in case of "Hair", "Haair" and "Haaair"
body: <p>Suppose there is three strings "Hair", "Haair" and "Haaair" , When i use grep -E '^Ha{1}' , it returns all the former three words, instead i was expecting only "Hair", as i have asked return a line which starts with H and is followed by letter 'a' exactly once. </p>