Reaction Mechanism - Structure and Reactivity; Reaction Profiles and Mechanism; Aliphatic Nucleophilic Substitution; Aromatic Nucleophilic Substitutions; Aliphatic Electrophilic Substitution; Aromatic Electrophilic Substitution; Electrophilic addition to Carbon-Carbon Multiple bond; Addition to Carbon-Heteroatom Multiple Bond; Elimination Reactions; Pericyclic Reactions; Abbreviation