This document contains a compilation of surgical tutorials by Dr. Bashir Bin Yunus. It begins with definitions and characteristics of various types of surgical infections. Common organisms that cause surgical infections are discussed, including Staphylococci, Streptococci, Pneumococci, and various gram-negative bacteria. Three main types of infections of significance in surgical patients are described in detail: surgical site infections, which can be superficial, deep, or involve organs/spaces; bloodstream infections like bacteremia and septicemia; and systemic inflammatory response syndrome. Classification criteria and signs of infection are provided for each type.