An abstraction with a rather modern essence, likely invented to meet the academic needs of Western mindset. When seven notes are articulated following the natural ascending order, it is referred to as an octave, Ṭhāṭa, Krama, Mela, or scale. The descending movement is simply named Avaroha. Considering the existence of twelve semitones and the requirement of seven of these to create a Ṭhāṭa, Vyaṅkatamukhī's Caturdaṇḍiprakāśikā indicates the presence of seventy-two different scales. Paṇditjī Viṣṇunārāyaṇa Bhātakhaṇḍe later selected ten of these with the intention of classifying approximately one hundred ninety-five principal Rāga in the Hindustani music system. However, many musicians do not agree with this classification. Currently, the major scale is identified with the Bilāvala Ṭhāṭa: SRGMPDN. Each Ṭhāṭa is named after a Rāga that utilizes those specific notes, and beneath each one, a certain number of Rāga are grouped, often having nothing in common except for the presence of the same notes. Following is the description proposed by Paṇditjī Viṣṇunārāyaṇa Bhātakhaṇḍe:

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1. Kalyāṇa  SRGmPDN
2. Bilāvala  SRGMPDN
3. Khamāj  SRGMPDn
4. Bhairava  SrGMPdN
5. Pūrvī  SrGmPdN
6. Mārwa  SrGmPDN
7. Kāfī  SRgMPDn
8. Āsāvarī  SRgMPdn
9. Bhairavī  SrgMPdn
10. Toḍī  SrgmPdN

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The number of Rāga can only be considered approximate and relative solely to the research conducted by Paṇditjī Viṣṇunārāyaṇa Bhātakhaṇḍe. Considering this classification, we have:

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1. Scale utilizing the augmented fourth degree
2. Natural scale
3. Scale utilizing the diminished seventh degree
4. Scale utilizing the diminished second and sixth degrees
5. Scale utilizing the diminished second and sixth degrees and the augmented fourth degree
6. Scale utilizing the diminished second and augmented fourth degrees
7. Scale utilizing the diminished third and seventh degrees
8. Scale utilizing the diminished third, sixth, and seventh degrees
9. Scale utilizing the diminished second, third, sixth, and seventh degrees
10. Scale utilizing the diminished second, third, sixth, and seventh degrees, and the augmented fourth degree

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It is evident that these scales have been associated with the names of certain Rāga for mnemonic purposes.

To this classification, a system of three groups Auḍuva, Ṣāḍava, and Sampūrṇa, called Jati, is added, referring to the use of five, six, and seven notes, respectively. According to Hindustani musicology, the use of at least five notes is essential to define any Rāga melody. The exception to the rule is the Rāga Mālaśrī, which uses only four notes. Rāga that gives names to the reference scales are called Melakartā (the lord of scales), Janaka Rāga (father of Rāga), and Āśraya Rāga (which provides refuge to Rāga). However, it must be noted that this is mere academic speculation; in reality, there are often no relationships between Rāga belonging to the same Ṭhāṭa. Furthermore, each scale loses its character once it is expressed through a Rāga.

In the Western system, there are seven scales derived from the major scale.

The first is the natural major scale corresponding to the Bilāvala Ṭhāṭa. In the Western system, it is called the Ionian scale, with half-tone intervals placed between the III and IV degrees and between the VII and VIII degrees. Taking the note C as the tonic, this will be called the C Ionian scale.

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Shifting the tonic up by one degree yields the Dorian scale with half-tone intervals placed between the II and III degrees and between the VI and VII, corresponding to the Kāfī Ṭhāṭa. It should be emphasized that the resulting scale becomes the D Dorian scale, but what matters to us in this case are the tonal relationships within the scale.

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Moving the tonic up by two degrees yields the Phrygian scale with half-tone intervals placed between the I and II and between the V and VI degrees, corresponding to the Bhairava Ṭhāṭa. In this case, the resulting scale will be the E Phrygian scale.

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Moving the tonic up by three degrees yields the Lydian scale with half-tone intervals placed between the IV and V and between the VII and VIII degrees, corresponding to the Kalyāṇa Ṭhāṭa. In this case, the resulting scale will be the F Lydian scale.

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Moving the tonic up by four degrees yields the Mixolydian scale with half-tone intervals placed between the III and IV and between the VI and VII degrees, corresponding to the Khamāj Ṭhāṭa. In this case, the resulting scale will be the G Mixolydian scale.

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Moving the tonic up by five degrees yields the Aeolian scale with half-tone intervals placed between the II and III and between the V and VI degrees, which has no corresponding scale in Paṇditjī Viṣṇunārāyaṇa Bhātakhaṇḍe's system. In this case, the resulting scale will be the A Aeolian scale.

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Moving the tonic up by six degrees yields the Locrian scale with half-tone intervals placed between the I and II and between the VI and V degrees, corresponding to the Māravā Ṭhāṭa. In this case, the resulting scale will be the B Locrian scale.

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With this system, each major scale can generate a series of new scales that, while retaining the same notes, assume their autonomy in relation to the degree that gradually takes on the role of the tonic of each scale. Thus, all Dorian scales, for example, will be equal to each other, having the same constitution and note distances. This holds true for all modal scales in the Western system and is evident in the Western system since the tonic is relative.

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If, instead, we choose the melodic minor scale as the starting point:

The first is the melodic minor scale, which has no correspondences in Paṇditjī Viṣṇunārāyaṇa Bhātakhaṇḍe's system, with half-tone intervals placed between the II and III degrees and between the VII and VIII degrees.

Shifting the tonic up by one degree yields the Dorian minor scale with a lowered second degree, with half-tone intervals placed between the I and II degrees and between the VI and VII, which has no correspondences in Paṇditjī Viṣṇunārāyaṇa Bhātakhaṇḍe's system.

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Moving the tonic up by two degrees yields the Lydian augmented scale with half-tone intervals placed between the V and VI and between the VII and VIII degrees, which has no correspondences in Paṇditjī Viṣṇunārāyaṇa Bhātakhaṇḍe's system.

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Moving the tonic up by three degrees yields the Lydian dominant or Mixolydian scale with an augmented fourth degree, with half-tone intervals placed between the IV and V and between the VI and VII degrees, which has no correspondences in Paṇditjī Viṣṇunārāyaṇa Bhātakhaṇḍe's system.

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Moving the tonic up by four degrees yields the Mixolydian scale with a diminished sixth degree or Hindu, with half-tone intervals placed between the III and IV and between the V and VI degrees, which has no correspondences in Paṇditjī Viṣṇunārāyaṇa Bhātakhaṇḍe's system.

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Moving the tonic up by five degrees yields the Locrian scale with a diminished third degree, with half-tone intervals placed between the II and III and between the IV and V degrees, which has no correspondences in Paṇditjī Viṣṇunārāyaṇa Bhātakhaṇḍe's system.

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Moving the tonic up by six degrees yields the Super Locrian scale with half-tone intervals placed between the I and II and between the III and IV degrees, which has no correspondences in Paṇditjī Viṣṇunārāyaṇa Bhātakhaṇḍe's system.

It should be noted that the Ṭhāṭa Āsāvarī, Pūravī, Bhairavī, and Toḍī do not have corresponding modal scales in the Western system.

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The term Thaat also indicates the frets of a fretted string instrument.