Kirtan or Kirtana (Punjabi: ਕੀਰਤਨ, Sanskrit: "praise, eulogy"; also Sankirtan) is call-and-response chanting or "responsory" performed in India's devotional traditions. A person performing kirtan is known as a kirtankar. Kirtan practice involves chanting hymns or mantras to the accompaniment of instruments such as the harmonium, tablas, the two-headed mrdanga or pakawaj drum, and karatal hand cymbals. It is a major practice in Vaisnava devotionalism, Sikhism, the Sant traditions, and some forms of Buddhism, as well as other religious groups. For Monier-Williums kirtana is “mentioning, repeating, saying, telling” but not a mode of singing. The Sanskritic wor(l)d view did not allow kirtana to be a mode of singing. However, in the context of Bengal, Bihar, Jharkhand, Orrissa, Tripura and Assam, the Eastern and North-Eastern region of the Indian geo-politics, kirtana is something more than that — something excess (rather than that of residue of some Hindusthani marga-songs) with rich variations of innovative raginis and talas. It has different sub-types.
Read more about Kirtan: The Basics of Kirtana, Kirtan and The Bhakti Movement, As A Given Name, In The West