Matching 0, 1, or More Occurrences
* and +
* matches zero or more occurrences of the preceding character. The fewest possible occurrences of a pattern will satisfy the match.
Example: a*b will match b, ab, aab, aaab, aaaab, and so on.
+ matches one or more occurrences of the preceding character.
Example: a+b will match ab, aab, aaab, aaaab, and so on, but not just b.