What is the meaning of OM?

Meaning of om symbol:



Om is one of the most important mantras of Hinduism (Sanatan Dharma), as you see most of the mantras in Sanatan cultural books starts with om. It is a creation of positive vibes. it is the simple sound with complex meaning. It is the original vibration of the universe. 

Basically "OM" is not a symbol, It is actually a Mantra.
It is sound. It has three sound itself. "aaauuuummm","Aum". The 1st sound is "A" then "U" and the last sound is "M".
basically, this mantra is from origin to deep sleep. 
If you chant om, it connects you to the universe. This is a sound, which is already we all have inside us and even it always present in universe. 

Once just sit in a silent place and just concentrate inside yourself you'll connect with the universe through om. 
Chanting of "OM" can connect you with chakras inside you. 
According to Sanatan dharma, in a human body we have seven chakras.
 
1. मूलाधार चक्र

2. स्वाधिष्ठान चक्र

3. मणिपुर चक्र

4. अनाहत चक्र

5. विशुद्ध चक्र

6. आज्ञा चक्र

7. सहस्त्रार चक्र

These chakras have energy "OM" this mantra has that power to connect with the power of chakras. 
"Om" creates vibration around us. Chanting of om once in a day can give us power to fight against any disease any fear or any situation.

Does om mean God?

Buddhism and Jainism also strongly associate with Om. They strongly believe that the 1st created sound by God is "OM". basically, it doesn't mean God. It is a sound of power and energy. It is a sound of universe. It creates vibration and that vibration is powerful. 

Chanting of "OM" is the way to God. It can connect you with that power. Because God, that power is somewhere inside you. The important part is you have to find it out and it is possible only when you connect with yourself. 
That power never dies. 
Whenever you'll stuck in your life, you can't understand what is right or wrong. Just keep clam and chant, connect with yourself. You'll definitely find the answer, the solution. 
Try it once, it will work and then you' ll get to know the actually meaning of "OM." 
and you'll understand why om is so powerful.