Islam is built on five
بُنِيَ الْإِسْلَامُ عَلَى خَمْسٍ: شَهَادَةِ أَنْ لَا إِلَهَ إِلَّا اللَّهُ وَأَنَّ مُحَمَّدًا رَسُولُ اللَّهِ، وَإِقَامِ الصَّلَاةِ، وَإِيتَاءِ الزَّكَاةِ، وَحَجِّ الْبَيْتِ، وَصَوْمِ رَمَضَانَ
Buniya-l-islamu 'ala khams: shahadati an la ilaha illa-llahu wa anna Muhammadan rasulullah, wa iqami-s-salah, wa ita'i-z-zakah, wa hajji-l-bayt, wa sawmi Ramadan.
"Islam is built on five: testifying that there is no god but Allah and that Muhammad is the Messenger of Allah, establishing prayer, giving zakat, pilgrimage to the House, and fasting in Ramadan."
Narrated by Ibn Umar. Sahih al-Bukhari 8, Sahih Muslim 16 · Nawawi's Forty · #3
A short reflection
The structure of a Muslim's life. Anything else we add sits on top of these five.