(1) Introduction
      (a) Importance of Interactions
      (b) Different Physical Regimes
(2) Catalogs
      (a) Interactions
      (b) Pairs
(3) Analytic Tools
      (a) Dynamical Friction
            (i)   Derivation of Retarding Force
            (ii)  Special Cases
            (iii) Applications of Dynamical Friction
      (b) Tidally Driven Evaporation
            (i)   Tidal (Jacobi/Roche) Limit
            (ii)  Satellite Evaporation/Destruction
      (c) Adiabatic (Slow) Encounter
      (d) Impulse (Fast) Encounter
(4) Numerical Simulations : Methods
(5) Numerical Simulations : Results
      (a) Flyby & Tidal Tails
      (b) Major Mergers
            (i)   Global Behaviour
            (ii)  Behaviour of Stars
            (iii) Behaviour of Gas
            (iv) Fueling Starbursts & AGN
      (c) Minor Mergers & Satellite Accretion
(6) Merger Relics
      (a) Elliptical Galaxy Formation
      (b) Counter-Rotating Disks
      (c) Polar Ring Galaxies
      (d) Shell Galaxies
      (e) Tidal Origin of Dwarf Galaxies