x = %w[alpha bravo charlie delta echo foxtrot]
# Get the initial letters
a = x.collect {|w| w[0..0]}       # %w[a b c d e f]
# Get the string lengths
b = x.collect {|w| w.length}       # [5, 5, 7, 5, 4, 7]
# map is just an alias
c = x.map {|w| w.length}           # [5, 5, 7, 5, 4, 7]

