In the first example: we’re matching those lines match the String “No” at the beginning of the line. Lines 21 and 29 satisfies this match from the fortunes file.
In the second example: were matching those lines in /etc/passwd file that begins with the character string “stu0”.
The capability to match at the beginning of a line is very powerful. Think of the possibility of needing to match header records; where the first set of characters at the beginning of the line will designate the record type.