Episode #125 of the Stack Overflow podcast is here. We talk Tilde Club and mechanical keyboards. Listen now
3 of 6 added 336 characters in body

Jelly, 13 bytes


All test cases are at TryItOnline


Œlf“aeiou”L%2 - Main link takes an argument - s
Œl            - lowercase(s)
   “aeiou”    - string of lowercase vowels
  f           - filter - keep only the vowels
          L   - length - the number of vowels
           %2 - modulo 2

Non-competing, 6 bytes (since I just added the function Øc)


Test cases also at TryItOnline

Same as above, but Øc yields the English vowels, 'AEIOUaeiou'