The Pillars of Islam (Arkaan al-Islam), the five duties incumbent on every Muslim: Shahadah, the Muslim profession of faith; Salah, or ritual prayer, performed in a prescribed manner five times each day; Zakah, the alms tax levied to benefit the poor and the needy; Sawm, fasting during the month of Ramadan; and Hajj, the major pilgrimage to Makkah.
Imam Nawawi 
records in his Arba`een:
On the authority of `AbdUllah ibn `Umar 
, RasoolAllah 
said:
“Islam is built upon five: witnessing that there is no God but Allah ﷻ and that Muhammad is the Messenger of Allah ﷻ; establishment of the prayer; payment of the Zakah; Hajj of the House [of Allah]; and the fast of Ramadan.”
(Bukhari and Muslim)
Shahadah
Here, RasoolAllah gives the analogy that Deen is like a building which is held up by five things. The central pillar from these five is the first; bearing witness that there is no God but Allah ﷻ, and Muhammad is His Messenger. The other four supplement this and can only be put into place once there is a central foundation. If any one of these pillars is missing, the building isn’t complete and will inevitably fall.
Salah
Prayer, as a pillar in faith, is emphasised in the Qur’an consistently. Allah ﷻ continuously commands us to establish our five daily prayers with steadfastness, and the Qur’an has mentioned the word ‘Salah’ 67 times. It has been said by Shaykh Ahmad ibn Zayni Dahlan in his book of prayer, that Salah is the foundation of one’s religion. Whoever has upheld his Salah has upheld his religion, and whoever has neglected his prayers has neglected his religion. For this reason, Salah should be emphasised and is the first thing a mureed will promise to fulfil when they give ba`yah.
Zakah
Payment of Zakah is an integral part of faith for one who fulfils the conditions of being able to give it. It creates ease for others, and is a means of bringing blessings into one’s earnings. Often, Allah ﷻ has mentioned the establishment of Salah and Zakah together. Each year an individual should work out their excess wealth and must give 2.5% of that excess wealth as Zakah.
Hajj
Performing Hajj is another pillar in the faith and according to some narrations is mentioned after Ramadan in the Hadith. However, it doesn’t have the same weight as Ramadan, to fast in Ramadan is a bigger duty upon a Muslim. Hajj only becomes Fard upon a person if he has the ability to go for Hajj and have enough money left at home to continue living. The rites of Hajj are many and take place in the month of Dhul Hijjah.
Sawm
The last pillar mentioned in the Hadith is to fast in the month of Ramadan. Refraining from food, drink, bad thoughts and sexual activity during daylight hours is done in the 9th lunar month and is fard upon every sane Muslim who has reached the age of puberty. The purpose behind fasting is to attain closeness to Allah ﷻ by putting our own desires aside and focusing on our relationship with Allah ﷻ. The Devils are shackled, and performing good deeds becomes easier for the Muslim. This not only demonstrates Allah’s ﷻ Mercy by giving us a means of changing ourselves, but it also shows us what we truly are capable of in terms of worship.
To conclude, the Five Pillars form the basis of Islam and must be fulfilled. Doing so is a requirement of a Muslim, and he/she should become well acquainted with the obligations surrounding these pillars. Perfecting what is required will lead onto perfection of actions that are desirable, ultimately leading to the pleasure of Allah ﷻ.