Filtration is a process that involves the separation of solids from a liquid or a gas with the use of a filter media. Early human civilizations have utilized rudimentary filtration processes for water purification. The advancement of filtration technology in recent years has resulted in many applications in the industry and improvements in our quality of life. Filtration is used extensively in many industries to carry out product recovery, ventilation, or water treatment and purification. Most of the current research in filtration technology is focused on the development of novel membranes. Dynamic cross-flow filtration is one of the most recent innovations in filtration technology that employs the use of dynamic membranes to carry out solid-liquid separation. In Chapter 3, two of the main conventional filtration techniques are described in detail: gas filtration and solid-liquid filtration. The mechanisms of the different modes of filtration, namely, the dead-end and cross-flow filtration, are discussed with their respective advantages and disadvantages. This is followed by a short discussion about the application of both air and solid-liquid filtration in various industries. The development of modern filtration technology as well as future prospective and challenges in filtration are also discussed.