Solat Fardhu is the solat that must for a muslim to perform it. It have 5 times per day in which are Subh, Zuhr, Asr, Maghrib and Ishak.
The one who not performing the Solat Fardhu will be asked when there are in Barzakh, and who did not perform it will get punishment.
For Subh, it has 2 rakaat, for Zuhr, Asr and Isyak they have 4 rakaat per day. Meanwhile for Maghrib prayer is performed for 3 rakaat only.
From Sahih Muslim:
مَا مِنْ عَبْدٍ مُسْلِمٍ يُصَلِّي لِلَّهِ كُلَّ يَوْمٍ ثِنْتَيْ عَشْرَةَ رَكْعَةً تَطَوُّعًا غَيْرَ فَرِيضَةٍ إِلاَّ بَنَى اللَّهُ لَهُ بَيْتًا فِي الْجَنَّةِ
Fajr | Dhuhr | Asr | Maghrib | Isha' |