ऊँ, OM and AUM all have the same meaning, which is the universal name of the Lord. It symbolises everything — the seen and unseen, known and unknown, the three worlds, and beyond. ऊँ is written differently throughout the world. The Sanskrit symbol (ऊँ) is probably the most commonly used and recognized. It is also said to represent Lord Ganesha. The top curve is HIS head, the bottom curve is HIS stomach, the side stroke is HIS trunk, and the chandra bindu (half moon with a dot) at the top is a modaka (the favorite sweet) in HIS hand.
ऊँ गं गणपतये नमो नमः
OM gam gaNapataye namo namah
This is Lord Ganesha’s mantra. It combines his bija (seed) sound, “gam” followed with “praise be to Ganapati.” We use this mantra to invoke Lord Ganesha so we can merge ourselves with His supreme knowledge, tranquility and peace. This is also used before beginning a journey or starting any new endeavor … as Lord Ganesha is the Supreme remover of all obstacles.
ऊँ श्री कृष्ण शरणं मम
OM Shree Krishna sharanam mama
Lord Krishna is my shelter.
ऊँ नमः शिवाय
OM namaḥ śivāya
I offer my prostrations to Lord Shiva.
ऊँ श्री राम, जाय राम, जाय जाय राम
OM śrī rāma, jāya rāma, jāya jāya rāma
OM and victory to Lord Rāma, victory, victory to Lord Rāma!