The Department of Computer Science & Engineering 
STUART C. SHAPIRO: CSE
115 C

Computer science is the study of procedures that are or could be carried out in the real world by physical (including biological, mechanical, and electronic) agents.See my position paper, What Is Computer Science?
Example: To determine if a number (decimal, integer) is divisible by 3, add its digits. If the result is divisible by 3, so is the original number.