Various forms to create an unique identifier by hash digest

gistfile1.sh

#Taken from http://stackoverflow.com/questions/8996820/how-to-create-md5-hash-in-bash-in-macos

echo "this will be encrypted" | md5
# 72caf9daf910b5ef86796f74c20b7e0b

md5 <<< 'this will be encrypted'
# 72caf9daf910b5ef86796f74c20b7e0b

md5 -s 'this will be encrypted'
# MD5 ("this will be encrypted") = 502810f799de274ff7840a1549cd028a

md5 -qs 'this will be encrypted'
# 502810f799de274ff7840a1549cd028a

#######
# Note: MD5 always produces the same hash. The reason you find the output different from the example given above is due to a 
# point that has been made in the comments. The first two examples use the trailing newline character to produce the hash. To 
# avoid that, you can use:
#######

echo -n "this will be encrypted" | md5
# 502810f799de274ff7840a1549cd028a