Pakar (also rendered pakad — literally "catch" or "grasp" in Hindi) is the melodic fingerprint of a raag. While the thaat tells you which notes a raag uses and the vadi/samvadi tell you which notes are emphasised, the pakar is what makes a raag itself: a short, characteristic phrase (typically 3-7 notes) that no other raag uses in quite the same way.
A trained listener identifies a raag in seconds because they hear its pakar. The artist, during alap, typically introduces the pakar early — often in the first minute — so the listener knows where they are. From then on, the pakar recurs as a touchstone: every time the artist returns to it, the raag is re-affirmed.
Some pakars are simple. The pakar of Raag Yaman uses the characteristic phrase Ni Re Ga Ma# Pa (rendered in sargam) — those five notes in sequence are unmistakably Yaman. The pakar of Raag Bhairon involves a slow descent through the komal (flat) Re and Dha. Raag Darbari is identified by a particular meend (glide) on the komal Dha and Ni.
Pakars are passed down within gharanas. Two different gharanas may have slightly different pakars for the same raag, reflecting different lineages' interpretations. But the core pakar is shared across the tradition — it is what makes a raag a recognisable entity rather than just a scale.