Colloidal systems are mixtures where tiny particles, known as colloids, are dispersed throughout a continuous medium, such as a liquid or gas. These particles are larger than molecules but too small to be seen with the naked eye, typically ranging from 1 nanometer to 1 micrometer in size. Common examples include milk, fog, and paint, where the dispersed particles remain suspended and do not settle out over time. In colloidal systems, the properties of the mixture can differ significantly from those of the individual components. The stability of colloids is influenced by factors like temperature, pH, and the presence of surfactants, which can help prevent the particles from clumping together. Understanding colloidal systems is essential in various fields, including food science, pharmaceuticals, and materials science.