The term unix operating system is identified in base64 scheme by the sequence dW5peCBvcGVyYXRpbmcgc3lzdGVt, while the MD5 signature is equal to 4c9a841fe5ed343a5388fccf4be4a376. The ASCII encoding of unix operating system in hexadecimal notation is 756e6978206f7065726174696e672073797374656d.