: Maa Durga Mantra :-

There are various Mantras which are recited to revere the 'Mother' or 'Ma' as every devout Hindu calls Her.

Below I present some:

1) Asato Ma sadgamaya
Tamaso Ma Jyotirgamaya
Mrityur Ma Amritam gamaya

Which means:
From untruth, lead me to the Truth,
From Darkness, Lead me towards the Light,
From Death, Lead me to Life Eternal.

Ma does not mean 'mother'..its an 'avyaya' used for negation (write Mayank)

2) Sharanaagata dinaarta
Paritraana paraayane
Sarvasyaarti harey Devi
Naraayani namostute

Which means:
Salutations be to you, O Mother
You who are intent on saving the downtrodden
and distressed that come under your refuge.
Oh Devi! you remove the suffering of everyone

The following Mantra of Ma, is one of my favourites as it can be said anytime of the day, and anytime during your life, to pray for benediction for yourself and all your loved ones.

3) Om Sarva mangala Maangalye
Shivey Sarvaartha Saadhikey
Sharanye Trayambikey Gauri
Naraayani Namostutey

Which means:
Oh Gauri Ma!, consort of Lord Shiva,
You, who bestow auspiciousness on all,
And fulfill everyone's' wishes,
I prostrate myself before Thee,
Take me under your care.

The following Mantras describe the various qualities of Ma:
I have picked up 3 and I generally like to say them during Navratra as they are rather simple to remember and recite:

4) Ya Devi Sarvabhuteshu
Shakti Rupena Sanshtita
Namastasyai Namastasyai Namastasyai
Namo Namaha

Which means:
Prostrations unto Thee, O Devi (Ma)
who dwells in all beings in the form of Shakti (Energy)

5)Ya Devi Sarvabhuteshu
Budhi Rupena Sansthita
Namastasyai Namastasyai Namastsyai
Namo Namaha

Which means:
Prostrations unto Thee O Devi (Ma)
who resides in all beings as Intelligence (Wisdom)

6)Ya Devi Sarva bhuteshu
Laxmi Rupena Sansthita
Namastasyai Namastasyai Namastasyai
Namo Namaha

Which means:
Prostrations unto Thee O Devi (Ma)
who resides in all beings in the form of Laxmi (abundance

7) Gauri Mantra for:

Acheiving child, son, spouse, prosperity

Gauraageem Dhrut Pankaja

Trinaya naam Shvetaambaraam

Sinha gaam Chandrod Bhaashit Shekharaam Smit mukheem

Dobhhyarhu vahteem gadaam

Vidhi Chandraambuj yochi kaam tridasheiha

Sampoojitaam dhrid va yom Gaureem

Maana sapam kaje Bhagavateem Bhakteshta daam taam bhaje

The Mantra describes the smiling countenance of Gauri Mata

and requests the fulfillment of desire.

A mala (rosary) of 108 beeds is recommended to be chanted.

The beej (seed) Mantra of Gauri Mata

Aum Hreem Shreem Glaum ga Gaureem Geem Svaahaa

8) Shri Kali-Mata Mantra

Aum Eim Hreem Kleem Sheem Kaaleeshwari (aa like in far, ee like in feel)

Sarva Jana Mano haarini Sarva mukha Stambhini

Sarba raaj vash karee sarva dushta Nirdalani (t like in tea)

Sarva Stree Purushaa Karshinee

vadhee Shrinkhalaa Strotaya Trotaya (d like in 'the')

Sarva Shatroon Bhanjaya (oo like in soot)

Bhanjaya Dvesheen Nirdalaya Sarvaan

Stambhaya Stambhaya Mohnaa Strena

Dveshina Muchaataya Uchaataya

Sarvam vasham karu karu svaaha

Dehi dehi sarvaa Kaal raatri Kaamini

Ganeshvaryei Namaha

The following mantra protects against violence and helps improve life in general.
It is the first stanza of the Argala Stotra :

Jayanti Mangalaa Kaali Bhadrakaali Kapaalini
Durgaa Shamaa Shivaa Dhatri Swahaa Swadhaa namostute.