Om – ॐ – What means?
It is the smallest manŧra (मंत्र). It is also called mūl-manŧra; mūl (मूल) means fundamental and primordial. Some also call it praṇav-manŧra. ‘Praṇav’ (प्रणव) means strong/powerful.
A shlok (श्लोक) is a Sanskṛiŧ verse, typically of two line.
A manŧra is a phrase (or rarely a word) used for meditation and chanting.
Sacred ancient Indian texts like Veđ (वेद), are collections of shlok/s. Some of these shlok/s are used as manŧra/s.
It is a common practice to begin other manŧra/s with Om, like –
1. ‘Om namaḥ Shivāya’ – ॐ नमः शिवाय,
2. ‘Om shānŧi(ħ) shānŧi(ħ)’ – ओम शांति: शांति:.
Jainism, Buđđhism and Sikhism originated from India after Hinđūism. These religions adopted some of the Hinđū philosophies and practices. These religions have their own forms and understandings of ‘Om’.
Many followers of these religions believe that ‘Om’ is the ultimate, hyper or super-natural sound!
In ĐevaNāgarī, this word can be written as ‘ओम्’ or ‘ओम’. It is general practice in Hinđī to drop the last ‘halant’ (‘्‘). So ‘ओम’ is generally preferred over ‘ओम्’.
The spelling ‘ओम’ is used in literature (mostly as noun); while the symbol ‘ॐ’ is used for religious purposes.