Karaṇa or unit of movement

Karaṇa is a “unit of movement” and not just a body’s movement. Karaṇa is the is the harmonious coordination of the victorious prāṇāyāma (ujjāyī prāṇāyāma), engagement of prāṇic centres (prāṇa-ādhāra-prayoga), body movements (anga-calanam), focused gaze (dṛṣṭi), posture (āsana) all co-regulated with mental focus and presence (aśithila sthiti) and  throughout a relatively constant unit of time (laya) into an harmonious flow (Samūdāya-vahanam).

The essential components of a karaṇa are: 

mātrā = count

ujjāyī prāṇāyāma = victorious prāṇāyāma / co-regulation of breath (ana) and vital energy (prāṇā)

prāṇa-ādhāra-prayoga = engagement of prāṇic centres

nāda =  mystical inner sound (tuned/pitch)

anga-calanam = body’s movements

dṛṣṭi = focused gaze

āsana = posture

aśithila sthiti  = mental presence

laya =  unit of time, mental absorption.

Indeed, the components of a Karaṇa is not limited to the above mentioned components. It may includes other components like: mudrā (attitudinal position of limbs), bandha (prāṇic locks), kriyā-śuddhi (active purification), different kind of prāṇāyāma-s (co-regulation and control of prāṇa and breath) and anything which can nicely fit into it.