This chapter reviews the fundamental principles governing the feeding of bulk solids from storage bins, bunkers, and stockpiles, with emphasis on the integrated design of hoppers, feeders, and discharge chutes. The interaction between hopper flow patterns and feeder performance is examined as a critical determinant of reliable, uniform discharge. Key design objectives for feeders are outlined, including capacity control, uniform draw-down across hopper outlets, stability of flow, and minimisation of segregation, wear, and power demand. A comprehensive overview of commonly used feeder types is presented, including vibratory, belt, apron, reciprocating plate, plough, rotary table, screw, tube, and rotary valve feeders, together with their operating principles, advantages, limitations, and typical applications. Attention is given to hopper-feeder interfacing, the need for increasing feeder capacity in the direction of feed, and the consequences of poor design through an illustrative case study. The chapter concludes with guidance on feeder selection based on material properties, particle size, and process requirements, providing a foundation for sound engineering judgment in bulk solids handling practice.