No. Then the automaton would accept strings that start with any number of 'a'.
Rule 6. ZERO or More Instances
* in a regular expression
means "match the preceding character zero or many times".
A* matches any number (including zero) of
|| ZERO or more 'a'|
||b, ba, baa, baaa, baaaa, ...|
|| Ø, a, ab, aaa, ababb, bbb, ...|
zero or more characters, each character an 'a' or 'b'
|| Ø, A, ABC, zw$nn, ...|
zero or more characters, no character a digit
|| Ø, a, aaa, aaab, abbb, b, bbb, ...|
zero or more 'a', followed by zero or more 'b'
In the above, Ø is the "empty string" — the string containing no characters. This sounds odd, but it is like a bank account with no money. It is useful to talk about the account, even it it is empty.
Stephen Kleene (1909-1994) was one of the early investigators of regular expressions and finite automata. The "Kleene star" is often used in computer science. It is a phrase you should know. Kleene pronounced his name "klay-nee", but often people pronounce it "klee-nee".
[fr]*og match "frog" ?