Colloidal suspensions and their interfaces are ubiquitous in nature and have attracted the interest of scientists for many decades, and find numerous applications in several industrial branches. Colloids are widely accepted as a versatile model system for atoms and molecules as their rich phase behaviour is analogous to that of atomic and molecular systems. The typical colloidal length and time scales make it possible to directly observe colloidal particles in real-time using video and confocal microscopy. Advanced colloid chemistry techniques enable tuning of the chemical and physical properties of the particles, allowing development of unique colloidal model systems.