Literally, "sutra" means “stitch.” It is a short verse containing potent spiritual knowledge. When a group of such short verses are brought together, they “stitch” together the whole of knowledge.
Particular sutras can be used for the purpose of structured samyama practice, as described in the Yoga Sutras of Patanjali. The use of sutras in samyama can have dramatic effects on the course of the enlightenment process and can also lead to the manifestation of siddhis (powers).