what is a geetham ?

Carnatic music is the form of Indian classical music that had its origins in South India. Geethams are the simplest music forms in Carnatic music.
Carnatic music is of a Melodic music form and is typically a monophonic song with improvised variations.

Some Geethams contain sections rather than the defined divisions (pallavi etc). They often have no sangathis or variations, with each swara (the notes) of Indian music are Shadjamam(Sa), Rishabham(Ri), Gandharam(Ga), Madhyamam(Ma), Panchamam(Pa), Dhaivatam(Da) and Nishadam(Ni) taking one syllable of the sahithya. The Geetham is sung without repetition from beginning to end. However most Geethams are concluded by repeating a portion of the opening part.
Geethams are set in medium tempo and the flow of the music is natural. The theme of the Sahithyam (lyrics) is to praise God. Students Learn these Geethams after a course in the preliminary Swara Exercises and Alankaras.

There are two forms of Geethams:
1. Sanchari or Samanya Geethams
2. Lakshana Geethams

SANCHARI GEETAMS/SAMANYA GEETHAMS :
Samanya Geethams are the simple ordinary Geethams and are called by other names such as Sadharana Geetham or Sanchari Geetham.

LAKSHANA GEETAMS
In Lakshana Geethams, the sahithyam, instead of being praise of God, enumerates in so many words, the lakshana of the Raga, in which it is composed-giving amongst other details, its Vakra Swaras, Graha, Nysa, Amsa Swarams and lastly its parent (Melakartha) Raga. Most Lakshana Geethams have been composed by Purandara Dasa, who is known as the father of Carnatic Music.