Soundarya Lahiri is a powerful divine prayer(stotra) partly revealed and partly composed by Great Universal Master Shri Sankara Bhagavatpada to express the devotion and praise the beauty of Devi Mahatripura Sundari. This stotra is a devotional hymn loaded with beautiful literary ornaments(alankaras). It has more than thirty two commentaries on it by famous spiritual Masters. That alone says it all about its extraordinary significance!
Each shloka (verse) is an extremely powerful mantra and has deeper tantric meanings and effects. Every sloka has its own yantra(mystical diagram) and specific method of chanting along with offerings to please Tripura Sundari Devi to achieve a definite goal as described in our Scriptures
While there are several legends to the source of this stotra, it is commonly believed that Shri Sankara Bhagavatpada got it from Lord Shiva at Kailasa as 100 slokas. Out of these there were 41 slokas called Ananda Lahiri (Waves of Bliss or Happiness) and the remaining 59 slokas were lost which was then recomposed by Shri Sankara Bhagavatpada. These slokas were called Soundarya Lahiri (Waves of Beauty). However in practice, all the 100 slokas are referred as Soundarya Lahiri.