fromFrom stackoverflow...:
comm -23 file1 file2
comm -23 file1 file2
-23-23 suppresses the lines in file2 (-2-2) and the lines that appear in both (-3-3), leaving only the unique lines from file1. The files have to be sorted (they are in your example) but if not, pipesort them through sort first. With process substitution:
comm -23 <(sort file1) <(sort file2)
See the man page here
-1 suppress column 1 (lines unique to FILE1)
-2 suppress column 2 (lines unique to FILE2)
-3 suppress column 3 (lines that appear in both files)