Ranjani is a Carnatic raga, which is also sometimes written as Ranjini.
[1][2] It is an asymmetric pentatonic scale, which is pleasing and has been more popular in last 50 years.
[1] It figures in ragamalikas, slokams, vrittams and light popular songs, as it is a pleasing scale.
[1][2] The notes in this scale are chathushruthi rishabham, sadharana gandharam, prati madhyamam, chathusruthi dhaivatam in arohana and additional kakli nishadham in avarohanam, in place of sadharna rishabham (see pictures).
S - is a catch phrase that is unique to ragam Ranjani (where N3.