Namaz is a Persian word that means worship of Allah, performed according to the teachings of the Holy Prophet Muhammad (PBUH). Salah is obligatory for Muslims five times every day. 

How many prayers in a day?

1. Fajr: Dawn
2. Dhuhr: Noon
3. Asr: Afternoon
4. Maghrib: Sunset
5. Isha: Night

There are hundreds of places where Allah has mentioned about (salah) namaz:

وَ يُـقِيْمُوْنَ الصَّلٰوةَ

Who believe in the unseen, establish prayer

Surah Baqarah ;Ayah No 03

IMPORTANCE OF NAMAZ

1- Allah has ordered us to offer prayer;

وَاَقِيۡمُوا الصَّلٰوةَ

And establish prayer

Surah Baqarah; Ayah No 43

2-Allah has ordered to seek help with sabar(patience) and salah;

وَاسۡتَعِيۡنُوۡا بِالصَّبۡرِ وَالصَّلٰوةِ ‌ؕ

And seek help through patience and prayer,

Surah Baqarah; Ayah No 45

3- Allah has ordered you to protect your salah especially the central (Asr)

حَافِظُوۡا عَلَى الصَّلَوٰتِ وَالصَّلٰوةِ

Maintain with care the [obligatory] prayers and [in particular] the middle prayer

Surah Baqarah; Ayah No 238

4- Reward for the people who offer prayers;

الَّذِیۡنَ اٰمَنُوۡا وَ عَمِلُوا الصّٰلِحٰتِ وَاَقَامُوا الصَّلٰوۃَ وَ اٰتَوُا الزَّکٰوۃَ لَہُمۡ اَجۡرُہُمۡ عِنۡدَ رَبِّہِمۡ

Indeed, those who believe and do righteous deeds and establish prayer and give zakah will have their reward with their Lord

Surah Baqarah; Ayah No 277

5-The people who offer prayers and do some other deeds their bad deeds will change the good as;

وَ الَّذِیۡنَ صَبَرُوا ابۡتِغَآءَ وَجۡہِ رَبِّہِمۡ وَ اَقَامُوا الصَّلٰوۃَ وَ اَنۡفَقُوۡا مِمَّا رَزَقۡنٰہُمۡ سِرًّا وَّ عَلَانِیَۃً وَّ یَدۡرَءُوۡنَ بِالۡحَسَنَۃِ السَّیِّئَۃَ اُولٰٓئِکَ لَہُمۡ عُقۡبَی الدَّارِ ﴿ۙ۲۲

And those who are patient, seeking the countenance of their Lord, and establish prayer and spend from what We have provided for them secretly and publicly and prevent evil with good - those will have the good consequence of [this] home -

Surah Raad; Ayah No 22

6- Allah has ordered Muslims to offer prayer in time;

اِنَّ الصَّلٰوۃَ کَانَتۡ عَلَی الۡمُؤۡمِنِیۡنَ کِتٰبًا مَّوۡقُوۡتًا ﴿۱۰۳

Indeed, prayer has been decreed upon the believers a decree of specified times.

Surah an Nisaa ;Ayah No 102