I am trying to reverse engineer two scripts that my perl programming book gave me but I can't find explanations in the book (I am sure they are there, but I am not having any luck) for some of the special characters. The first script is: 
while (<STDIN>) {
if (/a/i && /e/i && /i/i && /o/i && /u/i) {
print;
}
}

[download]
My question for the above script is what is the i outside of each of the // symbles. The second script is: 
hile (<>) {
print if
(/^[^aeiou]*a[^eiou]*e[^aiou]*i[^aeou]*o[^aeiu]*u[^aeio]*$ );
}

[download]
For this script I have a few more questions. It is supposed to parse a statement in order to determine if it shows each of the vowels in order. Why couldn't one just do this /a*i*o*u*/. Also what does e^aiou actually look for? e with any vowel character after it? Last, what is the purpose of the $ sign. I found this code very confusing. Thanks for your help!

In reply to Regular Expression by Socrates440

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